BIBLIOGRAFI TENTANG: PENYAKIT KUDA (TAHUN 2003 – 2017)

No. PENGARANG, JUDUL, TAHUN TERBIT

1 Anagha, G, Gulati BR, Riyesh T, Virmani N. (2017) Genetic characterization of equine herpesvirus 1 isolates from abortion outbreaks in India. Arch Virol,162(1):157-163. Abstract Equine herpesvirus 1 (EHV1) is a common pathogen of horses that causes upper respiratory tract disease, abortion, neonatal death and neurological disease. The neurological form of disease is called equine herpesvirus myeloencephalopathy (EHM). During the past decade, the incidence of EHM has been on the rise in Europe, North America, Australia and Asia. Some EHV1 isolates causing EHM exhibit a single-nucleotide polymorphism (SNP) in the DNA polymerase gene (ORF30) at position 2254 (A2254 to G2254). Further, based on polymorphism in the ORF68, EHV1 isolates have been classified into different groups. The aim of the present study was to estimate the genetic diversity of EHV1 and to determine the prevalence of the neuropathogenic genotype of EHV1 in India. Out of 133 clinical specimens from abortion cases in northern India, 56 were positive for EHV1 infection. Analysis of the A/G SNP by realtime PCR and sequence analysis revealed that 54 of 56 samples (96.43 %) were of the non-neuropathogenic genotype (A2254), while two (3.57 %) had the neuropathogenic marker (G2254). Sequence analysis of the polymorphic region of ORF68 of EHV1 isolates (n = 9) from India indicated that the Delhi/1998, Tohana-2/2013, Hisar-2/2014 and Hisar-15/1990 isolates belonged to group 4, while the Jind/1996, Rajasthan/1998, Delhi-3/ 2007 and Tohana-5/1996 isolates clustered within group 5. One isolate (Hisar-7/1990) exhibited SNPs at positions C710 and C713, forming a separate group. Here, we report for the first time the detection of neuropathogenic genotypes of EHV1 in India and show that Indian EHV1 isolates cluster within groups 4 and 5.

2 Basile, RC, et.al. (2017) A. Brazilian borreliosis with special emphasis on humans and horses. Braz J. Microbiol,48 (1):167-172. Abstract Borreliosis caused by Borrelia burgdorferi sensu lato is a cosmopolitan zoonosis studied world-wide; it is called Lyme disease in many countries of the Northern Hemisphere and Lyme-likeor Baggio-Yoshinari Syndrome in Brazil. However, despite the increasing number of suspectcases, this disease is still neglected in Brazil by the medical and veterinary communities.Brazilian Lyme-like borreliosis likely involves capybaras as reservoirs and Amblyomma andRhipicephalus ticks as vectors. Thus, domestic animals can serve as key carriers in pathogendissemination. This zoonosis has been little studied in horses in Brazil. The first survey wasperformed in the state of Rio de Janeiro, and this Brazilian Borreliosis exhibits many differ-ences from the disease widely described in the Northern Hemisphere. The etiological agentshows different morphological and genetic characteristics, the disease has a higher recur-rence rate after treatment with antibiotics, and the pathogen stimulates intense symptomssuch as a broader immune response in humans. Additionally, the Brazilian zoonosis is nottransmitted by the Ixodes ricinus complex. With respect to clinical manifestations, Baggio-Yoshinari Syndrome has been reported to cause neurological, cardiac, ophthalmic, muscle,and joint alterations in humans. These symptoms can possibly occur in horses. Here, wepresent a current panel of studies involving the disease in humans and equines, particularlyin Brazil. 3 Bielefeldt-Ohmann, Helle, et.al. (2017) Characterization of non-lethal West Nile Virus (WNV) infection in horses: Subclinical pathology and innate immune response. Mic Pathogen, 103: 71-79 Abstract Most natural West Nile virus (WNV) infections in humans and horses are subclinical or sub-lethal and non- encephalitic. Yet, the main focus of WNV research remains on the pathogenesis of encephalitic disease, mainly conducted in mouse models. We characterized host responses during subclinical WNV infection in horses and compared outcomes with those obtained in a novel rabbit model of subclinical WNV infection (Suen et al. 2015. Pathogens, 4: 529). Experimental infection of 10 horses with the newly emerging WNV-strain, WNVNSW2011, did not result in neurological disease in any animal but transcriptional upregulation of both type I and II interferon (IFN) was seen in peripheral blood leukocytes prior to or at the time of viremia. Likewise, transcript upregulation for IFNs, TNFa, IL1b, CXCL10, TLRs, and MyD88 was detected in lymphoid tissues, while IFNa, CXCL10, TLR3, ISG15 and IRF7 mRNA was upregulated in brains with histopathological evidence of mild encephalitis, but absence of detectable viral RNA or antigen. These responses were reproduced in the New Zealand White rabbits (Oryctolagus cuniculus) experimentally infected with WNVNSW2011, by intradermal footpad inoculation. Kinetics of the anti-WNV antibody response was similar in horses and rabbits, which for both species may be explained by the early IFN and cytokine responses evident in circulating leukocytes and lymphoid organs. Given the similarities to the majority of equine infection outcomes, immunocompetent rabbits appear to represent a valuable small-animal model for investigating aspects of non-lethal WNV infections, notably mechanisms involved in abrogating morbidity.

4 Cruz-Lopez, F,et.al. (2017) Equine viral arteritis in breeding and sport horses in central Spain. Res Vet Sci. Jan 27;115:88-91. Abstract Equine viral arteritis (EVA) may have a high economic impact on breeding stud farms due to the occurrence of EVA-associated abortion outbreaks and the ability of the virus to persist in carrier stallions. While the conse- quences of EVA in premises with sport horses are usually less severe, the first confirmed outbreak of EVA in Spain occurred in a riding club in Barcelona, but no data on the seroprevalence of EVA in sport horses have been reported in Spain. Given the importance of both Spanish Purebred (SP) breeding horses and sport horses for Spain's equine industry, the aim of this study was to determine and compare the seroprevalence of EVA in these two horse populations in central Spain. Serum samples from 155 SP breeding horses residing in 16 stud farms and 105 sport horses of different breeds housed in 12 riding clubs, collected between September 2011 and November 2013, were tested using a commercial EVA antibody ELISA test with a 100% sensitivity, and confirmed by seroneutralisation (SN) test. EVA seroprevalence in SP breeding horseswas higher 21.1% (95% CI 15.3– 26.8%) than that in sport horses (6.7%, 95% CI 1.89–11.45%). However, the primary use (breeding vs. sport) was not significantly associatedwith seropositivity to Equine Arteritis Virus (EAV), suggesting that different management factors do not affect EVA circulation in these two horse populations.

5 Decloedt, A, et.al. (2017) Right ventricular function during acute exacerbation of severe equine asthma. Equine Vet J. Jan 28. Abstract Background: Pulmonary hypertension has been described in horses with severe equine asthma, but its effect on the right ventricle has not been fully elucidated. Objectives: To evaluate right ventricular structure and function after a 1-week period of pulmonary hypertension secondary to acute exacerbation of severe equine asthma. Study design: Prospective study. Methods: A clinical episode of severe equine asthma was induced experimentally in six susceptible horses. Examinations in remission and on day 7 of the clinical episode included a physical examination with clinical scoring, echocardiography, arterial blood gas measurements, venous blood sampling for cardiac biomarkers, intracardiac pressure measurements, right ventricular and right atrial myocardial biopsies, airway endoscopy and bronchoalveolar lavage. After 1 month of recovery, physical examination, echocardiography and cardiac biomarker analysis were repeated. Echocardiographic and pressure measurements were compared with those in 10 healthy control horses. Results: All horses developed clinical signs of acute pulmonary obstruction. Right heart pressures increased significantly. Altered right ventricular function could be detected by tissue Doppler and speckle tracking echocardiography. Cardiac troponin concentrations did not increase significantly, but were highly elevated in one horse which exercised in the paddock prior to sampling. Focal neutrophil infiltration was present in two myocardial samples. Even in remission, asthmatic horses showed a thicker right ventricular wall, an increased left ventricular end-systolic eccentricity index at chordal level and decreased right ventricular longitudinal strain compared with controls. Main limitations: The induced clinical episode was rather mild and the number of horses was limited because of the invasive nature of the study. Conclusions: Pulmonary obstruction in asthmatic horses induces pulmonary hypertension with right ventricular structural and functional changes 6 Dumoulin, M, et.al. (2017) Evaluation of direct Etest for antimicrobial susceptibility testing of bacteria isolated from synovial fluid of horses using enrichment bottles. Vet J., 220:55-62. Abstract This study evaluated the Etest for direct antimicrobial susceptibility testing (AST) of bacteria from equine synovial specimens, incubated in BACTEC enrichment bottles. Ninety-four culture-positive broths were inoculated onto agar to directly determine the minimum inhibitory concentrations (MICs) of 13 antimicrobials, using the Etest (direct Etest). Results were compared with those obtained with the agar dilution reference method, the standard Etest, and the disc diffusion method, after subculture and standardisation of the inoculum. For categorical comparison of AST results, MICs were translated into susceptibility categories, using clinical breakpoints. The direct Etest predicted categorical susceptibility/ resistance of bacteria from equine synovial fluid with acceptable accuracy (overall categorical agreement, 91%) and was more reliable than the disc diffusion test. The direct Etest was less accurate than the standard Etest for generating MICs •} 1 log dilution relative to the reference method (overall essential agreement, 69% vs. 89%). As the Etest generated a high percentage of inaccuracies with trimethoprim and sulfadiazine, these were less suitable antimicrobial agents for inclusion. In conclusion, the direct Etest reliably predicted the susceptibility of isolates from equine synovial fluid for the tested antimicrobials, except for trimethoprim and sulfadiazine. Since it did not require subculture and preparation of a standardised inoculum, direct Etest results were available at least 24 h earlier than with other methods, which could facilitate the diagnosis of synovial infections. However, when accuracy is prioritised over speed for MIC determination, the standard Etest is preferred over the direct Etest.

7 Durward-Akhurst, SA, Valberg SJ. (2017) Immune-Mediated Muscle Diseases of the Horse. Vet Pathol. Jan 1:300985816688755. Abstract In horses, immune-mediated muscle disorders can arise from an overzealous immune response to concurrent infections or potentially from an inherent immune response to host muscle antigens. Streptococcus equi ss. equi infection or vaccination can result in infarctive purpura hemorrhagica (IPH) in which vascular deposition of IgA-streptococcal M protein complexes produces ischemia and complete focal infarction of skeletal muscle and internal organs. In Quarter Horse–related breeds with immune-mediated myositis, an apparent abnormal immune response to muscle antigens results in upregulation of major histocompatibility complex class (MHC) I and II on muscle cell membranes, lymphocytic infiltration of lumbar and gluteal myofibers, and subsequent gross muscle atrophy. Rarely, an inflammatory event results in myositis with subsequent systemic calcinosis characterized by a pathognomonic hyperphosphatemia and high fatality rate. This review presents an overview of these immune-mediated myopathies and highlights clinical and pathological features as well as the suspected pathophysiology. 8 FAVERJON, C., et.al. (2017) Early detection of West Nile virus in France: quantitative assessment of syndromic surveillance system using nervous signs in horses. Epidemiol. Infect., 145: 1044–1057 Abstract West Nile virus (WNV) is a growing public health concern in Europe and there is a need to develop more efficient early detection systems. Nervous signs in horses are considered to be an early indicator of WNV and, using them in a syndromic surveillance system, might be relevant. In our study, we assessed whether or not data collected by the passive French surveillance system for the surveillance of equine diseases can be used routinely for the detection of WNV. We tested several pre-processing methods and detection algorithms based on regression. We evaluated system performances using simulated and authentic data and compared them to those of the surveillance system currently in place. Our results show that the current detection algorithm provided similar performances to those tested using simulated and real data. However, regression models can be easily and better adapted to surveillance objectives. The detection performances obtained were compatible with the early detection of WNV outbreaks in France (i.e. sensitivity 98%, specificity >94%, timeliness 2·5 weeks and around four false alarms per year) but further work is needed to determine the most suitable alarm threshold for WNV surveillance in France using cost-efficiency analysis.

9 Franz M, et.al. (2017) Point Mutation in a Herpesvirus Co-Determines Neuropathogenicity and Viral Shedding. Viruses; 9(1). pii: E6. Abstract A point mutation in the DNA polymerase gene in equine herpesvirus type 1 (EHV-1) is one determinant for the development of neurological disease in horses. Three recently conducted infection experiments using domestic horses and ponies failed to detect statistically significant differences in viral shedding between the neuropatho- genic and non-neuropathogenic variants. These results were interpreted as suggesting the absence of a consistent selective advantage of the neuropathogenic variant and therefore appeared to be inconsistent with a systematic increase in the prevalence of neuropathogenic strains. To overcome potential problems of low statistical power related to small group sizes in these infection experiments, we integrated raw data from all three experiments into a single statistical analysis. The results of this combined analysis showed that infection with the neuropa-thogenic EHV-1 variant led to a statistically significant increase in viral shedding. This finding is consistent with the idea that neuropathogenic strains could have a selective advantage and are therefore systematically increasing in prevalence in domestic horse populations. However, further studies are required to determine whether a selective advantage indeed exists for neuropathogenic strains.

10 Immonen, IA,et.al. (2017) Long-term follow-up on recovery, return to use and sporting activity: a retrospective study of 236 operated colic horses in Finland (2006-2012). Acta Vet Scand.; 59(1): 5 Abstract Background: Surgical treatment of colic is expensive and complications may occur. Information on the prognosis and the use of the horse after surgery for colic is important for surgeons and owners. Current literature on return to athletic function after celiotomy is limited. The present study reviewed surgical cases of the Veterinary Teaching Hospital, Helsinki, Finland for 2006–2012. The aim was to follow the population of horses of different breeds for surgical findings, postsurgical complications, long-term recovery and prognosis. The findings and their influence on survival, return to previous or intended use and performance were assessed. Results: Most of the operated horses (82.6%; 195/236) recovered from anesthesia and 74.9% (146/195) were discharged. The total follow-up time was 8 years and 10 months and the median survival time 79.2 months. Age of the horse, location of the abdominal lesion (small vs. large intestine), incidence of postoperative colic, surgical site infection, incisional hernia or convalescence time after surgery, did not significantly affect the probability of performing in the previous or intended discipline after the surgery. A majority of the discharged horses (83.7%) was able to perform in the previous or intended discipline and 78.5% regained their former or higher level of performance. Operated horses had 0.18 colic episodes per horse-year during the long-term follow-up. The incidence of colic was 20.0% within the first year after surgery. Horses operated for large intestinal colic were 3.3-fold more prone to suffer postoperative colic than horses operated for small intestinal colic. The majority of the owners (96.3%) were satisfied with the veterinary care and nearly all (98.5%) evaluated the recovery after the colic surgery to be satisfactory or above. Conclusions: If the horse survives to discharge, prognosis for long-term survival and return to previous level of sporting activity and performance was good after colic surgery in a population of horses of different breeds. None of the factors studied were found to decrease the probability of performing in the same or intended discipline after surgery. The majority of horses were able to return to their previous activity and perform satisfactorily for several years after surgery.

11 Ishii, JB, et.al. (2017) Diagnosis of resistance alleles in codon 167 of the beta-tubulin (Cya-tbb-1) gene from third-stage larvae of horse cyathostomins. Res Vet Sci.;115: 92-95. Abstract Anthelmintic resistance is a serious problem for the control of equine gastrointestinal nematodes. In the present survey, 173 third stage larvae of cyathostomins were investigated from three different locations for the presence of the resistant genotype at codon 167 of the beta-tubulin gene, as this is the most prevalent mutation. The larvae from the state of Parana (n=67), Sao Paulo (n=54) and Santa Catarina (n=52), showed 61.2; 31.5 and 38.5% of the heterozygous resistant genotype - TTC/TAC, respectively. An unpublished mutation at codon 172 that results in a serine (S) to threonine (T) substitution was found in 17.9% (12/67) of samples from Parana; and 13.0% (7/54) of samples from Sao Paulo. We have compared the molecular diagnostic with the fecal egg count data (R2 = -0.79) from the same farms, and consider that the use of routine molecular diagnostic in individual larva may help to determine the population genetic distribution that is associated with drug failure

12 Joó, Kinga, et.al. (2017) Comparison of assays for the detection of West Nile virus antibodies in equine serum after natural infection or vaccination. Vet Imm and Immunopath, 183: 1–6 Abstract West Nile virus (WNV) mainly infects birds, horses and humans. Outcomes of the infection range from mild uncharacteristic signs to fatal neurologic disease. The main objectives of the present study were to measure serum IgG and IgM antibodies in naturally exposed and vaccinated horses and to com-pare results of haemagglutination inhibition test (HIT), enzyme-linked immunosorbent assay (ELISA) and plaque reduction neutralisation test (PRNT). Altogether 224 animals were tested by HIT for WNV antibodies and 41 horses were simultaneously examined by ELISA and PRNT. After primary screening for WNV antibodies, horses were vaccinated. Samples were taken immediately before and 3–5 weeks after each vaccination. McNemar’s chi- squared and percent agreement tests were used to detect concordance between HIT, ELISA and PRNT. Analyses by HIT confirmed the presence of WNV antibodies in 27/105 (26%) naturally exposed horses. Sera from 57/66 (86%) vaccinated animals were positive before the first booster and from 11/11 (100%) before the second booster. HIT was less sensitive for detecting IgG antibodies. We could detect postvac-cination IgM in 13 cases with IgM antibody capture ELISA (MAC-ELISA) and in 7 cases with HIT. WNV is endemic in Hungary and regularly causes natural infections. Protective antibodies could not be measured in some of the cases 12 months after primary vaccinations; protection is more reliable after the first yearly booster. Based on our findings it was not possible to differentiate infected from recently vaccinated horses using MAC-ELISA. HIT cannot be used as a substitute for ELISA or PRNT when detecting IgG, but it proved to be a useful tool in this study to gain statistical information about the tendencies within a fixed population of horses. 13 Lafri, Ismail, et.al. (2017) Seroprevalence of West Nile virus antibodies in equids in theNorth-East of Algeria and detection of virus circulation in 2014. Comparative Immunology, Microbiology and Infectious Diseases, 50: 8–12 Abstract West Nile fever (WNF) is a viral disease of wild birds transmitted by mosquitoes. Humans and equidscan alsobe affected and suffer from meningoencephalitis. In Algeria, since the 1994 epidemic, no dataon WNV circulation was available until 2012. In September 2012, a fatal human case of WNV neuro-invasive infection occurred in Jijel province. This study describes the first seroprevalence study of WestNile virus (WNV) antibodies conducted in the equine population in Algeria. During 2014, serum sampleswere collected from 293 equids (222 donkeys and 71 horses) asymptomatic and unvaccinated for WNVin three localities in Northeastern wetlands of Algeria. Antibodies against WNV were found in 51 samples(seroprevalence 17.4%) of sampled equids, distributed as follows: 19 (seroprevalence 26.8%) horses and32 (seroprevalence 14.4%) donkeys. Moreover 7 horses coming from Blida, in the center of Algeria, weretested before and after an 8- months stay in North-East Algeria. We observe a seroconversion in 2 horses,showing WNV circulation in 2014 in this specific region of Algeria. 14 Liu, Shiliang A., et.al. (2017) A recombinant fusion protein consisting of West Nile virus envelope domain III fused in-frame with equine CD40 ligand induces antiviral immune responses in horses. Veterinary Microbiology, 198: 51–58 Abstract West Nile Virus (WNV) is endemic in the US and causes severe neurologic disease in horses since its introduction in 1999. There is no effective pharmaceutical treatment for WNV infection rendering vaccination as the only approach to prevention and control of disease. The purpose of this study was to evaluate a recombinant vaccine containing domain III (DIII) of the WNV envelope glycoprotein with and without a natural adjuvant equine (CD40L) in producing virus neutralizing antibodies in horses. Serum IgG1 concentration in the groups of horses vaccinated with the DIII-CD40L + TiterMax and DIII-CD40L proteins were significantly increased (p < 0.05) after the second booster vaccination compared to other groups. Serum IgG4 and IgG7, IgG3 and IgG5 concentrations were not significantly increased among all groups. Western blot results showed that animals immunized with the DIII-CD40L protein (with or without TiterMax) exhibited the highest specific anti-DIII antibody activities after vaccinations. Moreover, animals immunized with the DIII- CD40L protein (with or without TiterMax) exhibited significantly stronger neutralization activity (p < 0.05) compared to other groups starting at week eight. The DIII-CD40L protein (with or without TiterMax) stimulated more CD8+ T cells, but not CD4+ T cells in equine PMBCs. The results demonstrated that vaccination with recombinant WNV E DIII-CD40L protein induced superior humoral and cellular immune response in healthy horses that may be protective against WNV-associated disease in infected animals. CD40L could be utilized as a non-toxic, alternative adjuvant to boost the immunogenicity of subunit vaccines in horses 15 Maile CA, et.al. (2017) A highly prevalent equine glycogen storage disease is explained by constitutive activation of a mutant glycogen synthase. Biochim Biophys Acta;1861(1 Pt A): 3388- 3398. Abstract Background: Equine type 1 polysaccharide storage myopathy (PSSM1) is associated with a missense mutation (R309H) in the glycogen synthase (GYS1) gene, enhanced glycogen synthase (GS) activity and excessive glycogen and amylopectate inclusions in muscle. Methods: Equine muscle biochemical and recombinant enzyme kinetic assays in vitro and homology modelling in silico, were used to investigate the hypothesis that higher GS activity in affected horse muscle is caused by higher GS expression, dysregulation, or constitutive activation via a conformational change. Results: PSSM1-affected horse muscle had significantly higher glycogen content than control horse muscle despite no difference in GS expression. GS activity was significantly higher in muscle from homozygous mutants than from heterozygote and control horses, in the absence and presence of the allosteric regulator, glucose 6 phosphate (G6P). Muscle from homozygous mutant horses also had significantly increased GS phosphorylation at sites 2+2a and significantly higher AMPKα1 (an upstream kinase) expression than controls, likely reflecting a physiological attempt to reduce GS enzyme activity. Recombinant mutant GS was highly active with a considerably lower Km for UDP-glucose, in the presence and absence of G6P, when compared to wild type GS, and despite its phosphorylation. Conclusions: Elevated activity of the mutant enzyme is associated with ineffective regulation via phosphorylation rendering it constitutively active. Modelling suggested that the mutation disrupts a salt bridge that normally stabilises the basal state, shifting the equilibrium to the enzyme's active state. General significance: This study explains the gain of function pathogenesis in this highly prevalent polyglucosan myopathy.

16 Maquart, M.,et.al. (2017) First Serological Evidence of West Nile Virus in Horses and Dogs from Corsica Island, France. Vector Borne Zoonotic Dis. 2017 Jan 11. Abstract West Nile virus (WNV) is widely distributed over the world, including Europe, Africa, and Asia and spread over the past two decades to North and South America. In the south of France, sporadic cases are frequently described and the virus is endemic in Italy with frequent cases and outbreaks. The aim of this study was to identify a possible WNV circulation in Corsica (French island in the Mediterranean Sea) in sheep, horses, and dogs as sentinel animals for the virus surveillance. In 2014, 386 blood samples were collected from 219 sheep, 96 horses, and 71 dogs, in 12 localities in Corsica, in the oriental coast of Corsica. Each sample was systematically tested for WNV immunoglobulin G using an in-house enzyme-linked immunosorbent assay (ELISA) with inactivated WNV as antigen. The result of the ELISA for the WNV antibody test on the sheep sera was all negative, whereas 9 of 96 horses (9.4%) and 6 of 71 dogs (8.4%) presented WNV antibodies. All the positive samples from horses and dogs were confirmed by serum neutralization test. Although no clinical case in humans and horses was reported to date, this report highlights the necessity to improve WNV surveillance in animals and humans, as well as in blood donors in Corsica

17 Manyweathers, J, et.al. (2017) Risk Mitigation of Emerging Zoonoses: Hendra Virus and Non- Vaccinating Horse Owners. Transbound Emerg Dis. Jan 4. Abstract Hendra virus was identified in horses and humans in 1994, in Queensland, Australia. Flying foxes are the natural host. Horses are thought to acquire infection by direct or indirect contact with infected flying fox urine. Humans are infected from close contact with infected horses. To reduce risk of infection in horses and humans, Australian horse owners are encouraged to vaccinate horses against the virus and adopt property risk mitigation practices that focus on reducing flying fox horse contact and contamination of horses’ environment with flying fox bodily fluids. This study investigates uptake of four Hendra virus risk mitigation practices in a sample of non- and partially vaccinating horse owners living close to previous Hendra virus cases. Protection motivation theory was used to develop a conceptual model to investigate risk perception and coping factors associated with uptake of risk mitigation practices. An online survey was administered via Facebook pages of veterinary clinics close to previous Hendra virus cases. Factors associated with uptake of risk mitigation practices were investigated using univariate and multivariate binary logistic regression. Belief that a risk mitigation practice would be effective in reducing Hendra virus risk was significantly associated with the uptake of that practice. Issues around the practicality of implementing risk mitigation practices were found to be the greatest barrier to uptake. Factors that relate to risk immediacy, such as nearby infection, were identified as more likely to trigger uptake of risk mitigation practices. The role of veterinarians in supporting Hendra risk mitigation was identified as more influential than that of respected others or friends. Findings from this study are being used to assist stakeholders in Australia responsible for promotion of risk mitigation practice in identifying additional pathways and reliable influencing factors that could be utilized for engaging and communicating with horse owners to promote Hendra virus risk mitigation behaviour 18 Petrić, Dušan, et.al. (2017) West Nile virus ‘circulation’ in Vojvodina, Serbia: mosquito, bird, horse and human surveillance. Mol Cell Probes.;31:28-36 Abstract Efforts to detect West Nile virus (WNV) in the Vojvodina province, northern Serbia, commenced with human and mosquito surveillance in 2005, followed by horse (2009) and wild bird (2012) surveillance. The knowledge obtained regarding WNV circulation, combined with the need for timely detection of virus activity and risk assessment resulted in the implementation of a national surveillance programme integrating mosquito, horse and bird surveillance in 2014. From 2013, the system showed highly satisfactory results in terms of area specificity (the capacity to indicate the spatial distribution of the risk for human cases of West Nile neuroinvasive disease - WNND) and sensitivity to detect virus circulation even at the enzootic level. A small number (n = 50) of Culex pipiens (pipiens and molestus biotypes, and their hybrids) females analysed per trap/night, combined with a high number of specimens in the sample, provided variable results in the early detection capacity at different administrative levels (NUTS2 versus NUTS3). The clustering of infected mosquitoes, horses, birds and human cases of WNND in 2014–2015 was highly significant, following the south-west to north-east direction in Vojvodina (NUTS2 administrative level). Human WNND cases grouped closest with infected mosquitoes in 2014, and with wild birds/mosquitoes in 2015. In 2014, sentinel horses showed better spatial correspondence with human WNND cases than sentinel chickens. Strong correlations were observed between the vector index values and the incidence of human WNND cases recorded at the NUTS2 and NUTS3 levels. From 2010, West Nile virus was detected in mosquitoes sampled at 43 different trap stations across Vojvodina. At 14 stations (32.56%), WNV was detected in two different (consecutive or alternate) years, at 2 stations in 3 different years, and in 1 station during 5 different years. Based on these results, integrated surveillance will be progressively improved to allow evidence-based adoption of preventive public health and mosquito control measures.

19 Pusterla N, et.al. (2017) Assessment of quantitative polymerase chain reaction for equine herpesvirus-5 in blood, nasal secretions and bronchoalveolar lavage fluid for the laboratory diagnosis of equine multinodular pulmonary fibrosis. Equine Vet J.;49(1):34-38. Abstract Reasons for performing study: The ante mortem diagnosis of equine multinodular pulmonary fibrosis (EMPF) relies on histopathological results and polymerase chain reaction (PCR)-positive equine herpesvirus (EHV)-5 testing of lung tissue. Polymerase chain reaction detection of EHV-5 in bronchoalveolar lavage fluid (BALF) is commonly used to support a diagnosis of EMPF. However, the diagnostic power of EHV-5 testing on BALF and other biological samples such as blood and nasal secretions has yet to be shown to support a diagnosis of EMPF. Objectives: To determine the frequency of detection and the viral loads of EHV-5 by quantitative PCR (qPCR) in blood, nasal secretions and BALF from horses confirmed with EMPF, healthy horses and horses with non-EMPF pulmonary diseases. Study design: Prospective study. Methods: The study population consisted of 70 adult horses divided into 4 groups based on a combination of clinical findings, cytology of BALF, imaging studies of the thoracic cavity and histopathology of pulmonary tissue: control group (n = 14), EMPF group (n = 11); inflammatory airway disease group (n = 32); and non-EMPF interstitial lung disease group (n = 13). For each horse, whole blood, nasal secretions and BALF were available for EHV-5 qPCR testing. Sensitivities, specificities and their respective 95% confidence intervals were calculated for viral loads from blood, nasal secretions and BALF. In addition, these measures were calculated for combined use of blood and nasal secretions. Results: The detection of EHV-5 in BALF was strongly associated with EMPF (sensitivity 91%, specificity 98.3%). Detection of EHV-5 in blood was, independent of the viral loads, strongly associated with EMPF with a sensitivity of 91% and specificity of 83.1%. The detection of EHV-5 in nasal secretions displayed the highest sensitivity (72.7%) and specificity (83.1%) at a level of >245,890 glycoprotein B target genes/million cells to support a diagnosis of EMPF. Dually positive blood and nasal secretions at any viral loads in support of EMPF yielded a sensitivity and specificity of 90% and 89.8%, respectively. 20 Rocheleau, JP, et.al. (2017) Characterizing areas of potential human exposure to eastern equine encephalitis virus using serological and clinical data from horses. Epidemiol Infect.;145(4):667-677. Abstract Eastern equine encephalitis (EEE) is a rare but severe emerging vector-borne disease affecting human and animal populations in the northeastern United States where it is endemic. Key knowledge gaps remain about the epidemiology of EEE virus (EEEV) in areas where its emergence has more recently been reported. In Eastern Canada, viral activity has been recorded in mosquitoes and horses throughout the 2000s but cases of EEEV in humans have not been reported so far. This study was designed to provide an assessment of possible EEEV human exposure by modelling environmental risk factors for EEEV in horses, identifying high-risk environments and mapping risk in the province of Quebec, Canada. According to logistic models, being located near wooded swamps was a risk factor for seropositivity or disease in horses [odds ratio (OR) 4·15, 95% confidence interval (CI) 1·16–14·8) whereas being located on agricultural lands was identified as protective (OR 0·75, 95% CI 0·62–0·92). A better understanding of the environmental risk of exposure to EEEV in Canada provides veterinary and public health officials with enhanced means to more effectively monitor the emergence of this public health risk and design targeted surveillance and preventive measures.

21 Welsh, CE, Duz M, Parkin TD, Marshall JF. (2017) Disease and pharmacologic risk factors for first and subsequent episodes of equine laminitis: A cohort study of free-text electronic medical records. Prev Vet Med.; 136: 11-18. Abstract Electronic medical records from first opinion equine veterinary practice may represent a unique resourcefor epidemiologic research. The appropriateness of this resource for risk factor analyses was explored aspart of an investigation into clinical and pharmacologic risk factors for laminitis. Amalgamated medicalrecords from seven UK practices were subjected to text mining to identify laminitis episodes, systemicor intra-synovial corticosteroid prescription, diseases known to affect laminitis risk and clinical signs orsyndromes likely to lead to corticosteroid use. Cox proportional hazard models and Prentice, Williams,Peterson models for repeated events were used to estimate associations with time to first, or subsequentlaminitis episodes, respectively. Over seventy percent of horses that were diagnosed with laminitis suf-fered at least one recurrence. Risk factors for first and subsequent laminitis episodes were found to vary.Corticosteroid use (prednisolone only) was only significantly associated with subsequent, and not ini-tial laminitis episodes. Electronic medical record use for such analyses is plausible and offers importantadvantages over more traditional data sources. It does, however, pose challenges and limitations thatmust be taken into account, and requires a conceptual change to disease diagnosis which should beconsidered carefully.

22 Yarnell K, Le Bon M,et.al. (2017) Reducing exposure to pathogens in the horse: a preliminary study into the survival of bacteria on a range of equine bedding types. J Appl Microb;122(1):23-29. Abstract Microbial strains included Streptococcus equi, Streptococcus zooepidemicus, Fusobacterium necrophorum, Dichelobacter nodosus and Dermatophilus congolensis. The bedding types tested were Pinus sylvestris (Scots pine shavings), Pinus nigra (Corsican pine shavings), Picea sitchensis (Sitka spruce shavings), Cannabis sativa (hemp) and chopped wheat straw. A suspension of each microbial strain was spread in triplicate on agar media and incubated in its optimal growth conditions. The viable count (colony-forming unit per ml) was determined for each bacterial strain for the five different bedding types. Pinus sylvestris bedding resulted in significantly less (P = 0·001) bacterial growth of all strains tested.

23 Aleman, M, Shapiro K, Sisó S, Williams DC, Rejmanek D, Aguilar B, Conrad PA. (2016) Sarcocystis fayeri in skeletal muscle of horses with neuromuscular disease. Neuromuscul Disord.;26(1):85-93. Abstract Recent reports of Sarcocystis fayeri-induced toxicity in people consuming horse meat warrant investigation on the prevalence and molecular characterization of Sarcocystis spp. infection in equids. Sarcocysts in skeletal muscle of equids has been commonly regarded as an incidental finding. In this study, we investigated the prevalence of sarcocysts in skeletal muscle of equids withneuromuscular disease. Our findings indicated that Sarcocystis fayeri infection was common in young mature equids with neuromuscular disease and could be associated with myopathic and neurogenic processes. The number of infected muscles and number of sarcocysts per muscle were significantly higher in diseased than in control horses. Sarcocystis fayeri was predominantly found in low oxidative highly glycolytic myofibers. This pathogen had a high glycolytic metabolism. Common clinical signs of disease included muscle atrophy, weakness with or without apparent muscle pain, gait deficits, and dysphagia in horses with involvement of the tongue and esophagus. Horses with myositis were lethargic, apparently painful, stiff, and reluctant to move. Similar to humans, sarcocystosis and cardiomyopathy can occur in horses. Although this study did not establish causality but a possible association (8.9% of cases) with disease; the assumption of Sarcocysts spp. being an incidental finding in every case might be inaccurate.

24 Alves Beuttemmüller E,et.al. (2016) Characterisation of the epidemic strain of H3N8 equine influenza virus responsible for outbreaks in South America in 2012. Virol J.;13:45. Abstract Background: An extensive outbreak of equine influenza occurred across multiple countries in South America during 2012. The epidemic was first reported in Chile then spread to Brazil, Uruguay and Argentina, where both vaccinated and unvaccinated animals were affected. In Brazil, infections were widespread within 3 months of the first reported cases. Affected horses included animals vaccinated with outdated vaccine antigens, but also with the OIErecommended Florida clade 1 strain South Africa/4/03. Methods: Equine influenza virus strains from infected horses were isolated in eggs, then a representative strain was subjected to full genome sequencing using segment-specific primers with M13 tags. Phylogenetic analyses of nucleotide sequences were completed using PhyML. Amino acid sequences of haemagglutinin and neuraminidase were compared against those of vaccine strains and recent isolates from America and Uruguay, substitutions were mapped onto 3D protein structures using PyMol. Antigenic analyses were completed by haemagglutination-inhibition assay using post- infection ferret sera.Results: Nucleotide sequences of the haemaglutinin (HA) and neuraminidase (NA) genes of Brazilian isolate A/equine/Rio Grande do Sul/2012 were very similar to those of viruses belonging to Florida clade 1 and clustered with contemporary isolates from the USA. Comparison of their amino acid sequences against the OIE-recommended Florida clade 1 vaccine strain A/equine/South Africa/4/03 revealed five amino acid substitutions in HA and seven in NA. Changes in HA included one within antigenic site A and one within the 220-loop of the sialic acid receptor binding site. However, antigenic analysis by haemagglutination inhibition (HI) assay with ferret antisera raised against representatives of European, Kentucky and Florida sublineages failed to indicate any obvious differences in antigenicity.Conclusions: An extensive outbreak of equine influenza in South America during 2012 was caused by a virus belonging to Florida clade 1, closely related to strains circulating in the USA in 2011. Despite reports of vaccine breakdown with products containing the recommended strain South Africa/03, no evidence was found of significant antigenic drift. Other factors may have contributed to the rapid spread of this virus, including poor control of horse movement.

25 Arent, Z, et.al. (2016) Leptospira interrogans serovars Bratislava and Muenchen animal infections: Implications for epidemiology and control. Vet Microbiol.;190:19-26. Abstract Strains of Leptospira interrogans belonging to two very closely related serovars – Bratislava and Muenchen – have been associated with disease in domestic animals, in particular pigs, but also in horses and dogs. Similar strains have also been recovered from various wildlife species. Their epidemiology is poorly understood. Two hundred and forty seven such isolates, from UK domestic animal and wildlife species, were examined by restriction endonuclease analysis in an attempt to elucidate their epidemiology. A representative sub-sample of 65 of these isolates was further examined by multiple-locus variable- number tandem repeat analysis and 22 by secY sequencing. Ten restriction pattern types were identified. The majority of isolates fell into one of three restriction endonuclease analysis pattern types designated B2a, B2b and M2a. B2a was ubiquitous and was isolated from 10 species and represented the majority of the horse and all dog isolates. B2b was very different, being isolated only from pigs, indicating that this type was maintained by pigs. The pattern M2a was reported for the majority of isolates from pigs but also was common in small rodents isolates. Five restriction pattern types were found only in wildlife suggesting that they are unlikely to pose a disease threat to domestic animals. Multiple-locus variable- number tandem repeat analysis identified six clusters. The REA types B2a and B2b were all found in one MLVA cluster while the majority of the M2a strains examined occurred in another cluster. The secY sequencing detected only one sequence type, clustered with other serovars of Leptospira interrogans

26 Amat JP, et.al. (2016) Estimating the incidence of equine viral arteritis and the sensitivity of its surveillance in the French breeding stock. Vet Microbiol.;192:34-42. Abstract Equine viral arteritis (EVA) may have serious economic impact on the equine industry. For this reason, it is monitored in many countries, especially in breeding stock, to avoid its spread during breeding activities. In France, surveillance is mainly based on serological tests, since mares are not vaccinated, but difficulties in interpreting certain series of results may impair the estimation of the number of outbreaks. In this study, we propose specific rules for identifying seroconversion in order to estimate the number of outbreaks that were detected by the breeding stock surveillance component (BSSC) in France between 2006 and 2013. A consensus among multidisciplinary experts was reached to consider seroconversion as a change in antibody titer from negative to at least 32, or as an eight-fold or greater increase in antibody level. Using these rules, 239 cases and 177 outbreaks were identified. Subsequently, we calculated the BSSC’s sensitivity as the ratio of the number of detected outbreaks to the total number of outbreaks that occurred in breeding stock (including unreported outbreaks) estimated using a capture-recapture model. The total number of outbreaks was estimated at 215 (95% credible interval 195–249) and the surveillance sensitivity at 82% (CrI95% 71–91). Our results confirm EVA circulation in French breeding stock, show that neutralizing antibodies can persist up to eight years in naturally infected mares and suggest that certain mares have been reinfected. This study shows that the sensitivity of the BSSC is relatively high and supports its relevance to prevent the disease spreading through mating 27 Autorino GL, et.al. (2016) Evolution of equine infectious anaemia in naturally infected mules with different serological reactivity patterns prior and after immune suppression. Vet Mic.;189:15-23. Abstract Information on equine infectious anaemia (EIA) in mules, including those with an equivocal reaction in agar gel immunodiffusion test (AGIDT), is scarce. For this, a study was conducted to evaluate the clinical, viral loads and pathological findings of two groups of naturally infected asymptomatic mules, respectively with a negative/equivocal and positive AGIDT reactivity, which were subjected to pharmacological immune suppression (IS). A non-infected control was included in the study that remained negative throughout the observation period. Throughout the whole study, even repeated episodes of recrudescence of EIA were observed in 9 infected mules, independently from their AGIDT reactivity. These events were characterized by mild, transient alterations, typical of the EIA acute form which are hyperthermia and thrombocytopenia, in concomitance with viral RNA (vRNA), peaks, that were higher in the Post-IS period, reaching peaks similar to those of horses during the clinical acute phase of EIA. Total tissue viral nucleic acid loads were greatest in animals with the major vRNA activity and in particular in those with negative/equivocal AGIDT reactivity. vRNA replication levels were around 10 to 1000 times lower than those reported in horses, with the animals still presenting typical alterations of EIA reactivation. Macroscopic lesions were absent in all the infected animals while histological alterations were characterised by lymphomonocyte infiltrates and moderate hemosiderosis in the cytoplasm of macrophages. On the basis of the above results, even mules with an equivocal/negative AGIDT reaction may act as EIAV3 reservoirs. Moreover, such animals could escape detection due to the low AGIDT sensitivity andtherefore contribute to the maintenance and spread of the infection.

28 Back H, et.al. (2016) Genetic variation and dynamics of infections of equid herpesvirus 5 in individual horses. J Gen Virol. 97(1):169-78. Abstract Equid herpesvirus 5 (EHV-5) is related to the human Epstein–Barr virus (human herpesvirus 4) and has frequently been observed in equine populations worldwide. EHV-5 was previously assumed to be low to non- pathogenic; however, studies have also related the virus to the severe lung disease equine multinodular pulmonary fibrosis (EMPF). Genetic information of EHV-5 is scanty: the whole genome was recently described and only limited nucleotide sequences are available. In this study, samples were taken twice 1 year apart from eight healthy horses at the same professional training yard and samples from a ninth horse that was diagnosed with EMPF with samples taken pre- and post-mortem to analyse partial glycoprotein B (gB) gene of EHV-5 by using next-generation sequencing. The analysis resulted in 27 partial gB gene sequences, 11 unique sequence types and five amino acid sequences. These sequences could be classified within four genotypes (I– IV) of the EHV-5 gB gene based on the degree of similarity of the nucleotide and amino acid sequences, and in this work horses were shown to be identified with up to three different genotypes simultaneously. The observations showed a range of interactions between EHV-5 and the host over time, where the same virus persists in some horses, whereas others have a more dynamic infection pattern including strains from different genotypes. This study provides insight into the genetic variation and dynamics of EHV-5, and highlights that further work is needed to understand the EHV-5 interaction with its host.

29 Back H,et.al. (2016) The first reported Florida clade 1 virus in the Nordic countries, isolated from a Swedish outbreak of equine influenza in 2011. Vet Microbiol.;184:1-6. Abstract Equine Influenza Virus (EIV) is a major cause of respiratory disease in horses and the virus constantly undergoes antigenic drift. Here we characterize and describe the HA1 and the NA genes of H3N8 within samples obtained from outbreaks in Sweden during November–December 2011. Both clade 1 and clade 2 viruses of the Florida sublineage were identified. The index case of clade 2 was transported to Sweden from Spain through the Netherlands, whereas the clade 1 had its origin from a Swedish stud farm. The clade 1 virus was efficiently spread between training yards by unvaccinated young horses, but vaccinated horses were also presented with clinical signs of respiratory disease. No virus of the Eurasian lineage was isolated during this outbreak. Clade 1 has previously been described in outbreaks in numerous of other countries, but this is the first time it has been detected in Sweden. The results from this study shows the importance of including both clade 1 and clade 2 of the Florida sublineage in equine influenza vaccines, supporting the ESP and OIE recommendations.

30 Bannai H, et.al. (2016) Improvement of an enzyme-linked immunosorbent assay for equine herpesvirus type 4 by using a synthetic-peptide 24-mer repeat sequence of glycoprotein G as an antigen. J Vet Med Sci.;78(2):309-11. Abstract To increase the sensitivity of an enzyme-linked immunosorbent assay (ELISA) for equine herpesvirus type 4 (EHV-4) that uses a 12-mer peptide of glycoprotein G (gG4-12-mer: MKNNPIYSEGSL) [4], we used a longer peptide consisting of a 24-mer repeat sequence (gG4-24-mer: MKNNPIYSEGSLMLNVQHDDSIHT) as an antigen. Sera of horses experimentally infected with EHV-4 reacted much more strongly to the gG4-24-mer peptide than to the gG4-12-mer peptide. We used peptide ELISAs to test paired sera from horses naturally infected with EHV-4 (n=40). gG4-24-mer ELISA detected 37 positive samples (92.5%), whereas gG4-12-mer ELISA detected only 28 (70.0%). gG4-24-mer ELISA was much more sensitive than gG4-12-mer ELISA.

31 Bannazadeh, Baghi H, Nauwynck HJ. (2016) Effect of equine herpesvirus type 1 (EHV-1) infection of nasal mucosa epithelial cells on integrin alpha 6 and on different components of the basement membrane. Arch Virol.;161(1):103-10. Abstract The respiratory mucosa is the common port of entry of equine herpesvirus type 1 (EHV-1) and several other alphaherpesviruses. An important prerequisite for successful host invasion of the virus is to cross the epithelial cell layer and the underlying basement membrane barrier. In the present study, an analysis was performed to see if an EHV-1 infection of nasal mucosa epithelial cells leads to damage of the underlying extracellular matrix proteins. Nasal mucosa explants were inoculated with EHV-1 and collected at 0, 24 and 48 hours post- inoculation (hpi). Then, double immunofluorescence staining was performed to detect viral-antigen-positive cells on the one hand and integrin alpha 6, laminin, collagen IV and collagen VII on the other hand. The area of these extracellular matrix proteins was measured in regions of interest (ROIs) at a magnifi-cation of 200X by means of the software imaging system ImageJ. ROIs were defined beneath uninfected and infected regions. In uninfected regions, 22-28 % of the ROI was stained for integrin alpha 6, 18-37 % for laminin, 14-38 % for collagen IV and 18-26 % for collagen VII. In infected regions, the percentage positive for integrin alpha 6 was significantly decreased to 0.1-9 % and 0.1-6 % after 24 and 48 hours of inoculation, respectively. Infection did not alter the percentages for laminin and collagen IV. For collagen VII, an increase in the percentage (from 18- 26 % to 28-39 %) could be observed underneath EHV-1-infected plaques at 48 hours of inoculation. In conclusion, the results revealed a substantial impact of EHV-1 infection on integrin alpha 6 and collagen VII, two important components of the extracellular matrix, which are associated with the basement membrane and may facilitate virus penetration via hijacked leukocytes to underlying tissues

32 Bartolomé Del Pino LE,et.al. (2016) Babesia caballi and Theileria equi infections in horses in Central-Southern Italy: Sero-molecular survey and associated risk factors. Ticks Tick Borne Dis.;7(3):462-9. Abstract Babesia caballi and Theileria equi are tick-borne pathogens, etiological agents of equine piroplasmosis that affect different species of Equidae causing relevantly important direct and indirect losses.A field study was conducted to evaluate the distribution of the equine piroplasms in an area of Central-Southern Italy and to identify correlated risk factors. Serum samples of 673 asymptomatic horses werecollected during spring- summer of 2013 to estimate the seroprevalence of the parasites within the studyarea using T. equi and B. caballi Antibody test kit (VMRD®, Inc, Pullman, WA,USA).The 273 seropositivesamples were subsequently tested by real time PCR to verify the presence of the genome of the piroplasms,indicative of the carrier status of the subjects. The variables chosen to identify which were the risk factorsassociated with the serological and PCR-positivity for each of the equine piroplasms were the following:gender, age, breed, access to pasture, altitude, land cover, climatic zone, soil type and province location(coastal/inland).The resulting overall seroprevalence for T. equi was 39.8% (268/673) and for B. caballi was 8.9% (60/673)while 70.3% of the PCR tested samples (185/263) were positive for T. equi and 10.3% (27/263) for B. caballi.The univariate and multiple logistic regression models were used to assess the association of the risk fac-tors with the different outcomes. The risk factors found to be associated with T. equi seropositivity weregender, age, breed, access to pasture, land cover, soil type and province location, while those associatedwith PCR-positivity were age, soil type and province location. As the number of B. caballi seropositivesubjects was limited, the multiple logistic regression model was performed only for the PCR-positivestatus, identifying climatic zone and soil type as the sole risk factors. In the study area, a major diffu-sion of T. equi, in terms of seropreva-lence and PCR-positivity was present when compared to that of B.caballi, probably related to the cumulative effect of the life-long infection of the former protozoan. Theidentification of risk factors relative to each piroplasm infection, specific to a study area, is important inthe development and improvement of tailored control and prevention programmes aimed at containinghealth and economic consequences.

33 Barton, AK, Pelli A, Rieger M, Gehlen H. (2016) Procalcitonin as a biomarker in equine chronic pneumopathies. BMC Vet Res.;12(1):281. Abstract Background: Procalcitonin (PCT), a precursor protein of the hormone calcitonin, is a sensitive inflammatory marker in human medicine, which is primarily used for diagnosis of bacterial sepsis, but is also useful in diagnosis of exacerbation of asthma and COPD. In this study, PCT was evaluated as a potential biomarker for different chronic pneumopathies in the horse using an equine specific ELISA in comparison to established clinical markers and different interleukins. Sixty-four horses were classified as free of respiratory disease, recurrent airway obstruction (RAO), inflammatory airway disease (IAD) or chronic interstitial pneumopathy (CIP) using a scoring system. PCT concentrations were measured in plasma (n = 17) and in the cell-free supernatant of bronchoalveolar lavage (n = 64). PCT concentrations were correlated to interleukins IL-1ß and IL-6 in BALF, clinical findings and BALF cytology. Results: The median PCT concentrations in plasma were increased in respiratory disease (174.46 ng/ml, n = 7) compared to controls (13.94 ng/ml, n = 10, P = 0.05) and correlated to PCT in BALF supernatant (rs = 0.48). Compared to controls (5.49 ng/ml, n = 15), median PCT concentrations in BALF supernatant correlated to the overall clinical score (rs = 0.32, P = 0.007) and were significantly increased in RAO (13.40 ng/ml, n = 21) and IAD (16.89 ng/ml, n = 16), while no differences were found for CIP (12.02 ng/ml, n = 12). No significant increases were found for IL-1 and IL-6 between controls and respiratory disease in general as well as different disease groups. Conclusions: Although some correlations were found between PCT in plasma, BALF supernatant and clinical scores, PCT in BALF does not seem to be a superior marker compared to established clinical markers. PCT in plasma seems to be more promising and a greater number of samples should be evaluated in further studies.

34 Barton, AK, Shety T, Bondzio A, Einspanier R, Gehlen H. (2016) Metalloproteinases and their inhibitors are influenced by inhalative glucocorticoid therapy in combination with environmental dust reduction in equine recurrent airway obstruction. BMC Vet Res.;12(1):282. Abstract Background: Procalcitonin (PCT), a precursor protein of the hormone calcitonin, is a sensitive inflammatory marker in human medicine, which is primarily used for diagnosis of bacterial sepsis, but is also useful in diagnosis of exacerbation of asthma and COPD. In this study, PCT was evaluated as a potential biomarker for different chronic pneumopathies in the horse using an equine specific ELISA in comparison to established clinical markers and different interleukins. Sixty-four horses were classified as free of respiratory disease, recurrent airway obstruction (RAO), inflammatory airway disease (IAD) or chronic interstitial pneumopathy (CIP) using a scoring system. PCT concentrations were measured in plasma (n = 17) and in the cell-free supernatant of bronchoalveolar lavage (n = 64). PCT concentrations were correlated to interleukins IL-1ß and IL-6 in BALF, clinical findings and BALF cytology. Results: The median PCT concentrations in plasma were increased in respiratory disease (174.46 ng/ml, n = 7) compared to controls (13.94 ng/ml, n = 10, P = 0.05) and correlated to PCT in BALF supernatant (rs = 0.48). Compared to controls (5.49 ng/ml, n = 15), median PCT concentrations in BALF supernatant correlated to the overall clinical score (rs = 0.32, P = 0.007) and were significantly increased in RAO (13.40 ng/ml, n = 21) and IAD (16.89 ng/ml, n = 16), while no differences were found for CIP (12.02 ng/ml, n = 12). No significant increases were found for IL-1 and IL-6 between controls and respiratory disease in general as well as different disease groups. Conclusions: Although some correlations were found between PCT in plasma, BALF supernatant and clinical scores, PCT in BALF does not seem to be a superior marker compared to established clinical markers. PCT in plasma seems to be more promising and a greater number of samples should be evaluated in further studies.

35 Bełżecki, G, Miltko R, Michałowski T, McEwan NR. (2016) Methods for the cultivation of ciliated protozoa from the large intestine of horses. FEMS Microbiol Lett.;363(2):fnv233. Abstract This paper describes cultivation methods for ciliates from the digestive tract of horses. Members of three different genera were successfully grown in vitro for short periods of time. However, only cells belonging to the genus Blepharocorys, which resides in the horse’s large intestine, were maintained for longer periods. This Blepharocorys culture was successfully grown in vitro after inoculation of freshly excreted horse faeces in culture medium containing a population of bacteria. The ciliates survived for over six months, and the density of their population varied between 1.7 × 103 and 2.4 × 103 cells mL−1. Favourable conditions for the prolonged cultivation of this ciliate were observed when the medium was prepared by mixing horse faeces and ‘caudatum’ salt solution in a 1:1 V/V ratio together with food (60% powdered meadow hay, 16% wheat gluten, 12% barley flour and 12% microcrystalline cellulose) supplied as 0.20 mg mL−1 culture per day 36 Bischofberger AS,et.al. (2016) Effect of Manuka honey gel on the transforming growth factor β1 and β3 concentrations, bacterial counts and histomorphology of contaminated full-thickness skin wounds in equine distal limbs. Aust Vet J.;94(1-2):27-34. Abstract In this experimental study of 10 Standardbred horses, five full-thickness skin wounds (2 × 1.5 cm) were created on one metacarpus and six similar wounds were created on the contralateral metacarpus. Wounds were assigned to three groups: noncontaminated control wounds; contaminated control wounds; contaminated wounds treated daily with 1 mL Manuka honey gel topically for 10 days. For the contaminated wounds, faeces were applied for 24 h after wound creation. In five horses wounds were bandaged and in the other five horses wounds were left without a bandage. Biopsies were taken on days 1, 2, 7 and 10 after wounding to evaluate the effects of Manuka honey gel, wound contamination and bandaging on TGF-β1 and TGF-β3 concentrations, aerobic and anaerobic bacterial counts, and histomorphology.

37 Boado A, López-Sanromán FJ. (2016) Prevalence and characteristics of osteochondrosis in 309 Spanish Purebred horses. Vet J.;207:112-7. Abstract Articular osteochondrosis (OC) is commonly reported in horses but there are no reports of its prevalence in the Spanish Purebred (SP). The objective of this study was to assess the prevalence and characteristics of OC of the tarsocrural, dorsal metacarpo-metatarsophalangeal and femoropatellar joints in the SP in a retrospective study. The data were obtained from the radiographs of 309 SP horses and the prevalence and characteristics of lesions were calculated. Osteochondral lesions at predilected sites were diagnosed in 48.8% of the horses. It was more common to find the presence of fragments (28.8%) than flattening of the subchondral bone contour (20.1%). The percentage with abnormal articular margins was 1.3% for the femoropatellar joint, 33.3% for the tarsocrural and 25% for the dorsal fetlock region, where flattening was more common than the presence of fragments; in the tarsus and stifle, fragments were more common. The severity of the disease in the dorsal fetlock area was higher in hindlimbs than in forelimbs. Femoropatellar lesions were rare. Osteochondrosis is a common disease in the SP and this study provides information about the prevalence of osteochondrosis lesions in the breed and the interrelationships between the joints

38 Bolfa P, Barbuceanu F, Leau SE, Leroux C. (2016) Equine infectious anaemia in Europe: Time to re- examine the efficacy of monitoring and control protocols? Equine Vet J.;48(2):140-2. Abstract Equine infectious anaemia (EIA) is a disease with an almost worldwide distribution and is of considerable importance to the equine industry, primarily because it is one of only 11 notifiable equine specific diseases listed by the World Organisation For Animal Health (OIE). Equine infectious anaemia is caused by EIAV (equine infectious anaemia virus), a blood-borne retrovirus belonging to the lentivirus genus [1]. It is unfortunate that the disease only receives significant attention when an EIA outbreak has a significant financial impact [2]. Equine infectious anaemia outbreaks have been reported in Belgium, Bosnia, Croatia, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Romania, Serbia, Slovenia and the UK between 2007 and 2014 [3]. In countries where EIA re-emerged after several years of absence such as in Belgium, Germany, Ireland and the UK, epidemiological studies suggested that equine biological products (such as blood plasma) imported from Italy or Romania were the source of the outbreaks. Moreover, several European countries (including Hungary, Poland and Serbia) have recently reported new EIA outbreaks and cases, underlining a wider extent of the disease in Europe than previously reported. 39 Boukraa, S, et.al. (2016) Diversity and ecology survey of mosquitoes potential vectors in Belgian equestrian farms: A threat prevention of mosquito-borne equine arboviruses. Prev Vet Med.; 124:58- 68. Abstract Emergence of West Nile Virus was recently recorded in several European countries, which can lead tosevere health problems in horse populations. Europe is also at risk of introduction of mosquito-borneequine alphavirus from Americas. Prevention of these arboviruses requires a clear understanding oftransmission cycles, especially their vectors. To characterize mosquito fauna, their ecology and iden-tify potential vectors of equine arboviruses in Belgium, entomological surveys of six equestrian farmslocated in the Wolloon Region were conducted during 2011–2012. The harvest of mosquitoes was basedon larval sampling (272 samples from 111 breeding sites) and monthly adults trapping (CO2-baited traps,Mosquito Magnet Liberty Plus). Among 51,493 larvae and 319 adult mosquitoes collected, morpholog-ical identification showed the presence of 11 species: Anopheles claviger (Meigen), An. maculipennis s.l.(Meigen), An plumbeus (Stephens), Culex hortensis (Ficalbi), Cx. territans (Walker), Cx. pipiens s.l. L., Cx. tor-rentium (Martini), Coquillettidia richiardii (Ficalbi), Culiseta annulata (Schrank), Aedes cantans (Meigen),Ae. geniculatus (Olivier). Molecular identification of Cx. pipiens species complex allowed the detection ofthree molecular forms, Pipiens (92.3%), Molestus (4.6%) and Hybrid (3.1%). Larvae of Cx. pipiens sl and Cx.torrentium were omnipresent and the most abundant species. Water troughs, ponds and slurry (liquidmanure) were the most favorable breeding sites of mosquito larvae. Based upon behavior and ecologyof the identified mosquito species, Studied Belgian equestrian farms seem to provide a suitable environ-ment and breeding sites for the proliferation of potential vectors of arboviruses and those being a realnuisance problem for horses and neighboring inhabitants.

40 Bouzalas, IG, et.al. (2016) Emergence of Equine West Nile Encephalitis in Central Macedonia, Greece, 2010. Transbound Emerg Dis. Dec;63(6):e219-e227. Abstract During the summer of 2010, an outbreak of West Nile virus (WNV) infections attributed to a lineage 2 WNV strain was reported among humans and horses in Central Macedonia, Northern Greece. Here, the clinical and laboratory investigation of horses that showed severe neurological signs due to WNV infection is being described. Specifically, between August and September 2010, 17 horses with neurological signs were detected. WNV infection was confirmed in all 17 clinical cases by applying laboratory testing. The duration of WNVspecific IgM antibodies in sera obtained from seven of the clinically affected horses was relatively short (10–60 days; mean 44 days). In the regional unit of Thessaloniki, (i) seroprevalence of WNV and fatality rate in horses were high (33% and 30%, respectively), and (ii) the ratio of neurological manifestations to- infections for this virus strain was high (19%). These observations indicate that the strain responsible for the massive human epidemic of 2010 in Greece was also highly pathogenic for horses. This is the first time that WNV infection has been documented in horses with clinical manifestations in Greece. WNV infection should be included in the differential diagnosis of horses with encephalitis in Greece. Introduction West Nile virus (WNV) is a mosquito-borne RNA virus that can infect a wide range of vertebrate hosts, including horses, birds and humans (Kulasekera et al., 2001; Ward et al., 2004). West Nile virus is maintained in nature in an enzootic cycle between ornithophilic mosquitoes and birds (Hurlbut, 1956; Rappole and Hub_alek, 2003). Horses and humans are regarded as dead-end hosts, as viraemia developed in them

41 Brilhante RS, et.al. (2016) Trends in antifungal susceptibility and virulence of Candida spp. from the nasolacrimal duct of horses. Med Mycol.;54(2):147-54. Abstract This was a cross-sectional study to investigate the antifungal susceptibility and production of virulence factors in strains of Candida isolated from the outlet and the lumen of the nasolacrimal duct of horses in the state of Ceara´ , Brazil. The samples were obtained from 103 horses. Sterile cotton swabs were used to collect the material from the outlet of the nasolacrimal duct and urethral probes, for the instillation of 2 ml of saline solution, were used to collect samples from the lumen of the nasolacrimal duct. A total of 77 Candida isolates were obtained, with C. famata, C. tropicalis, C. guilliermondii, and C. parapsilosis sensu lato as the most prevalent species. One isolate (C. glabrata) was resistant to caspofungin. One isolate was resistant only to fluconazole (C. Parapsilosis sensu lato), 11 were resistant only to itraconazole (7 C. tropicalis, 2 C. guilliermondii, 1 C. famata, 1 C. parapsilosis sensu lato), while eight C. tropicalis showed resistance to both azoles. Overall, 28 isolates produced phospholipases and 12 produced proteases. These results highlight the importance of investigating the antifungal susceptibility and virulence trends of Candida spp. from the microbiota of the nasolacrimal duct of horses

42 Burns, TA. (2016) Effects of Common Equine Endocrine Diseases on Reproduction. Vet Clin North Am Equine Pract. Dec;32(3):435-449. Abstract The equine metabolic syndrome (EMS), first described in 2002,1 is perhaps the most common endocrine disorder encountered in equine veterinary practice. The definition of the syndrome is currently held to include obesity (particularly regional adiposity), systemic insulin resistance (IR), and historical or current laminitis.2 However, this definition is likely ready for refinement based on the research effort that has been directed at characterization of EMS over the past 5 to 10 years; additional characteristics that are likely to be addressed in the case definition in the future include dyslipidemia, hypertension, altered circulating concentrations of biomarkers (including adipokines; eg, leptin and adiponectin), and altered reproductive cyclicity in mares. Subfertility and reproductive failure have been reported to be common in overconditioned equids, but the accompanying pathophysiology linking infertility to obesity in these animals is incompletely characterized to date. Links to human conditions leading to obesity and infertility, such as polycystic ovary syndrome, have been investigated, and although some similarities may exist, substantial species differences exist

43 Carossino M,et.al. (2016) Detection of equine arteritis virus by two chromogenic RNA in situ hybridization assays (conventional and RNAscope(®)) and assessment of their performance in tissues from aborted equine fetuses. Arch Virol., 161(11):3125-36. Abstract Equine arteritis virus (EAV) is the causative agent of equine viral arteritis, a respiratory and reproductive disease of equids. EAV infection can induce abortion in pregnant mares, fulminant bronchointerstitial pneumonia in foals, and persistent infection in stallions. Here, we developed two RNA in situ hybridization (ISH) assays (conventional and RNAscope_ ISH) for the detection of viral RNA in formalin-fixed paraffin- embedded (FFPE) tissues and evaluated and compared their performance with nucleocapsid-specific immunohistochemistry (IHC) and virus isolation (VI; gold standard) techniques. The distribution and cellular localization of EAV RNA and antigen were similar in tissues from aborted equine fetuses. Evaluation of 80 FFPE tissues collected from 16 aborted fetuses showed that the conventional RNA ISH assay had a significantly lower sensitivity than the RNAscope_ and IHC assays, whereas there was no difference between the latter two assays. The use of oligonucleotide probes along with a signal amplification system (RNAscope) can enhance detection of EAV RNA in FFPE tissues, with sensitivity comparable to that of IHC. Most importantly, these assays provide important tools with which to investigate the mechanisms of EAV pathogenesis.

44 Carfora V,et.al. (2016) A methicillin-resistant Staphylococcus aureus (MRSA) Sequence Type 8, spa type t11469 causing infection and colonizing horses in Italy. Pathog Dis.;74(4):ftw025. Abstract A Methicillin-resistant Staphylococcus aureus (MRSA) was isolated in Italy from a pathological sample of a mare presenting chronic purulent sinusitis and that had undergone frontal-sinus surgery three months before. Humans, horses, dogs and environmental samples were subsequently collected at the mare’s stable and at the Veterinary Hospital where the mare was operated/hospitalized, and screened for the presence of MRSA, that was detected from other horses and from the environment at both sites. All the MRSA isolates belonged to clonal complex (CC)8, ST8-t11469-SCCmec-IVa, and showed similar phenotypic and genetic multidrug resistance patterns and macrorestriction-PFGE profiles. The only MRSA detected from humans was a CC1, ST1-t127-SCCmec-IVa. This represents the first report of a clinical MRSA infection in a horse in Italy. This study also supports the opinion that improper use of antibiotics and hospitalization/surgery can represent risk factors for MRSA colonization/infection in horses, and that the environment is among important sources for exposure.

45 Cohen, N.D.,et.al. (2016) Use of Liposomal Gentamicin for Treatment of 5 Foals with Experimentally Induced Rhodococcus equi Pneumonia. J Vet Intern Med,;30: 322–325 Abstract Background: Adverse effects of, and bacterial resistance to, macrolides used to treat Rhodococcus equi infections have prompted search for clinically effective alternative antimicrobials. Liposomal gentamicin (LG) is effective against R. Equi in vitro and decreases tissue concentrations of R. equi in experimentally infected mice. Effectiveness of LG treatment of foals with R. equi pneumonia, however, has not been described. Hypothesis: Liposomal gentamicin is safe and effective for treating foals with R. equi pneumonia. Animals: Ten foals with experimentally induced R. equi pneumonia. Methods: Pilot treatment trial. Foals with pneumonia induced by intrabronchial instillation of R. equi were randomly allocated to receive either clarithromycin combined with rifampin (CLR + RIF) PO or LG IV, and followed by daily physical examinations and weekly thoracic ultrasonography and serum creatinine concentration determinations until the resolution of clinical signs. Treatment success was defined as the resolution of clinical signs and ultrasonographically identified pulmonary abscesses. Results: All 10 foals were successfully treated. Two of 5 foals treated with LG developed azotemia within 1 week; LG was discontinued and treatment switched to CLR + RIF for these foals. None of the CLR + RIF treated foals developed azotemia. Conclusions and Clinical Importance: Liposomal gentamicin IV can be effective for treatment of R. equi pneumonia, but nephrotoxicity indicates that an alternative dosing interval or route (such as nebulization) will be needed before LG is adequately safe for clinical use. Larger comparative trials will be needed to evaluate the relative efficacy of a safer LG dosage regimen.

46 Costa S, Sastre P,et.al. (2016) Development and evaluation of a new lateral flow assay for simultaneous detection of antibodies against African Horse Sickness and Equine Infectious Anemia viruses. J Virol Methods. 237:127-131. Abstract African horse sickness (AHS) and equine infectious anemia (EIA) are both notifiable equid specific diseases that may present similar clinical signs. Considering the increased global movement of horses and equine products over the past decades, together with the socio-economic impact of previous AHS and EIA outbreaks, there is a clear demand for an early discrimination and a strict control of their transmission between enzootic and AHS/EIA-free regions. Currently, the individual control and prevention of AHS or EIA relies on a series of measures, including the restriction of animal movements, vector control, and the use of several laboratory techniques for viral identification, amongst others. Despite being widely employed in surveillance programmes and in the control of animal movements, the available serological assays can only detect AHS- or EIA-specific antibodies individually. In this work, a duplex lateral flow assay (LFA) for simultaneous detection and differentiation of specific antibodies against AHS virus (AHSV) and EIA virus (EIAV) was developed and evaluated with experimental and field serum samples. The duplex LFA was based on the AHSV-VP7 outer core protein and the EIAV-P26 major core protein. The results indicated that the duplex LFA presented a good analytical performance, detecting simultaneously and specifically antibodies against AHSV and EIAV. The initial diagnostic evaluation revealed a good agreement with results from the AHS and EIA tests prescribed by the OIE, and it highlighted the usefulness of the new AHSV/EIAV duplex LFA for an on-field and point-of- care first diagnosis.

47 Cruz, F, Fores P,et.al. (2016) Seroprevalence and factors associated with equine herpesvirus type 1 and 4 in Spanish Purebred horses in Spain. Vet Rec.;178(16):398. Abstract Equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) have a worldwide distribution and cause respiratory disease, abortion, neonatal death and myeloencephalopathy in susceptible horses. Given the scarcity of serological EHV-1/EHV-4 data in Spain, the objective of this cross-sectional study was to estimate the seroprevalence of EHV-1/EHV-4 and to identify potential horse-level and stud farm-level factors associated with EHV-1/EHV-4 in the breeding Spanish Purebred (SP) horse population in central Spain. Serum samples from 334 SP unvaccinated horses, collected between September 2011 and November 2013 at 30 stud farms, were tested using a commercially available EHV-1/EHV-4 antibody ELISA and seroneutralisation as the World Organisation for Animal Health reference confirmation test. Data on factors putatively associated with seropositivity to EHV-1/EHV-4 were collected via a questionnaire and examined using logistic regression analysis. EHV-1/EHV-4 seroprevalence in the SP breeding population in central Spain, standardised for the sex distribution of the reference horse population, was 53.9 per cent (95 per cent confidence interval 44.0 per cent to 63.8 per cent). Increasing age, southern location of the stud farm, temperate climate during the summer, and a smaller surface area used for breeding activities in the farm were associated with increased odds for EHV- 1/EHV-4 seropositivity, whereas EHV-1/EHV-4 vaccination of other resident horses and separation of breeding mares from youngsters were protective factors.

48 Cruz, F, Fores P, et.al. (2016) Seroprevalence and factors associated with seropositivity to equine arteritis virus in Spanish Purebred horses in Spain. Equine Vet J;48(5): 573-7. Abstract Reasons for performing study: Equine viral arteritis (EVA), a disease caused by infection with the equine arteritis virus (EAV), is present in many European countries. In Spain, the last confirmed outbreak was reported in 1992 and there is a paucity of seroprevalence studies. The disease has a major impact on the equine breeding industry, which is mainly represented by Spanish Purebred (SP) horses in Spain. Objectives: To estimate the seroprevalence of EAV in the breeding SP horse population in central Spain and identify potential horse and studfarm level factors associated with seropositivity to EAV. Study design: Cross-sectional study. Methods: Individual serum samples from 555 SP horses, collected between September 2011 and November 2013 at 35 studfarms, were tested using a commercially available EAV antibody ELISA and seroneutralisation as the World Organisation for Animal Health reference confirmation test for samples with positive and equivocal results. Data on factors putatively associated with seropositivity to EAV were collected via a questionnaire and examined using random effects logistic regression for analysis of clustered data. Results: Equine arteritis virus seroprevalence in the SP breeding population in central Spain standar-dised for the sex distribution of the reference horse population, was estimated to be 16.8% (95% confidence interval 5.2–28.5%). Increasing numbers of breeding mares on the studfarm and increasing percentage of mares with reproductive problems during the last 12 months were identified as being positively associated with EAV seropositivity. Mares vaccinated against Equine herpesvirus-1 (EHV-1) and/or -4 (EHV-4) were also positively associated with EAV seropositivity. Conclusions: These findings are of importance to ensure appropriate biosecurity measures for studfarms are carried out and may help facilitate the development of an EVA surveillance programme in the SP breeding horse population.

49 Cui, J, Zhao Y, et.al. (2016) Equine Immunoglobulin and Equine Neutralizing F(ab')₂ Protect Mice from West Nile Virus Infection. Viruses.; 8(12). pii: E332. Abstract West Nile virus (WNV) is prevalent in Africa, Europe, the Middle East, West Asia, and North America, and causes epidemic encephalitis. To date, no effective therapy for WNV infection has been developed; therefore, there is urgent need to find an efficient method to prevent WNV disease. In this study, we prepared and evaluated the protective efficacy of immune serum IgG and pepsin-digested F(ab′)2 fragments from horses immunized with the WNV virus-like particles (VLP) expressing the WNV M and E proteins. Immune equine F(ab′)2 fragments and immune horse sera efficiently neutralized WNV infection in tissue culture. The passive transfer of equine immune antibodies significantly accelerated the virus clearance in the spleens and brains of WNV infected mice, and reduced mortality. Thus, equine immunoglobulin or equine neutralizing F(ab′)2 passive immunotherapy is a potential strategy for the prophylactic or therapeutic treatment of patients infected with WNV

50 Curto, E, et.al. (2016) Cytokine and chemokine profiles of aqueous humor and serum in horses with uveitis measured using multiplex bead immunoassay analysis. Vet Immunol and Immunopathol.;182: 43-51. Abstract Objective: To determine whether horses with clinically diagnosed Equine Recurrent Uveitis (ERU) andthose with Leptospirosis infection have a specific cytokine profile in their aqueous humor (AH) andserum that differs from horses with uveitis secondary to other ocular inflammatory processes and fromhorses with normal eyes.Animals studied: Twenty-five client-owned horses with uveitis that were presented to the North CarolinaState University Ophthalmology Service, and four University-owned horses without history or clinicalsigns of ocular disease.Procedure: Samples of AH and serum were obtained from horses with ERU (n = 13), acute or non-recurrentuveitis (UV; n = 7), uveitis secondary to infectious keratitis (IK; n = 5), and normal eyes (N; n = 4). Cytokinelevels in AH and serum were quantified using a multiplex bead immunoassay. Leptospiral antibody titersin serum and AH and PCR for Leptospiral DNA in AH were performed.Results: In the AH of horses with ERU, increased levels of IL-1a, IL-4, IL-6, IL-8, IL-12p70, FGF-2, G-CSF, andRANTES were measured compared to UV, IK and N eyes, but the differences were not significant. However,IL-10 was significantly higher in ERU eyes compared to IK and N (P = 0.029; 0.013), and IP-10 in ERU eyeswas significantly higher than in UV and N (P = 0.004). Furthermore, MCP-1 was significantly higher in ERUthan N (P = 0.04). In the serum, increased levels of IL-1a, IL-4, IL-6, IL-8, IL-12p70, fractalkine, and G-CSFwere measured in horses with ERU, but the levels were not significantly higher than those observed inUV, IK, or N horses. However, serum IP-10 levels in horses with ERU were significantly higher than inUV and N horses (P = 0.005) and MCP-1 levels were significantly higher in ERU than N (P = 0.03). Horseswith marked ocular inflammation had significantly higher serum levels of G-CSF, IL-1a, fractalkine, IL-13,IL-4, IL- 17a, IL-12p70, IFN- _, and MCP-1. Elevated IL-10 in AH was significantly associated with diseasechronicity, both overall and in ERU eyes (P = 0.049), and in horses with positive ocular leptospiral titersor leptospiral PCR, significant elevations of IL-10 (P = 0.0018; 0.0032) and IP-10 (P = 0.0342; 0.043) weredetected in the AH compared to leptospiral negative eyes.Conclusions: The antiinflam-matory cytokine IL-10 and the pro- inflammatory cytokine IP-10 appear toplay an important role in ERU. Further studies are needed to further clarify and characterize cytokineprofiles of specific ocular inflammatory diseases, but multiplex bead immunoassay technology showspromise as a diagnostically valuable tool.

51 Davitkov D, Vucicevic M,et.al. (2016) Molecular detection and prevalence of Theileria equi and Babesia caballi in horses of central Balkan. Acta Parasitol.;61(2):337-42. Abstract Equine piroplasmosis is significant tick-borne disease with wide distribution. The prevalence of equine piroplasmosis in Serbia, Montenegro and Bosnia and Herzegovina is unknown. In aim to obtain a first insight into the prevalence we performed molecular epidemiological study which included 142 horses, on seven locations in these three countries. We first performed PCR for the detection of a 450bp long section of the 18S rRNA of piroplasma-specific region. For all positive samples we have done multiplex PCR for the species detection. Species determination was further confirmed by sequencing PCR products of 10 randomly selected Theileria equi and all Babesia caballi samples. The overall prevalence rates in analysed region for T. equi and B. caballi were 22.5% and 2.1%, respectively. Possible risk factors (such as location, age, sex and activity) associated with PCR positivity were evaluated. Marked differences were found in prevalence between geographic areas. There was no significant association between positivity and age group. T. equi was more prevalent in females and farming horses. This is the first report on the molecular survey of T. equi and B. caballi in central Balkan. Further prevalence studies on definitive host and vectors in this region are necessary.

52 Dixon PM. (2016) Preventing haemorrhage in equine guttural pouch mycosis. Vet Rec.;178(2):42-3. Abstract THE guttural pouches (diverticulae of the eustachian tubes) are enigmatic structures in horses whose function remains unclear. Among their proposed functions are: cooling of the blood flowing through the internal carotid artery and thus cooling of the brain; equalising air pressures across the tympanic membrane; and acting as a resonating chamber for vocalisation (Freeman and Hardy 2012). Regardless of their function, guttural pouches contain many vital nerves and blood vessels lying superficially beneath their mucosa that are susceptible to injury in the presence of guttural pouch infections. Guttural pouches can suffer from a variety of microbial infections and in particular are a predilection site for Streptococcus equi (var equi), ie, strangles, infection. Because the guttural pouch mucosa is part of the common upper airway mucosal system, it can also be affected by all respiratory viral infections and thus guttural pouch mucosal inflammation occurs with all such infections.

53 Dominguez, M, et.al. (2016) Equine disease events resulting from international horse movements: Systematic review and lessons learned. Equine Vet J.;48(5):641-53. Abstract Reasons for performing study: An analysis of the factors leading to equine disease events was used to support the development of international recommendations for mitigating the risk of disease dissemination through sport horse movements (high health, high performance – ‘HHP’ horses). Objectives: A review was undertaken to identify the factors resulting in equine disease events following international movement of horses to draw lessons in support of the development of international recommendations for the safe movements of a specific subpopulation of horses: the HHP sport horses. Study design: Systematic review carried out in accordance with the PRISMA statement. Methods: The review covered disease events that occurred from 1995 to 2014, identified from the databases of the World Organisation for Animal Health (OIE) and international surveillance reports. Results: Overall, 54 disease events were identified, of which 7 were contained in post arrival quarantine and the others resulted in the introduction of pathogens into importing countries. For 81% of the introductions, the OIE recommendations applicable to the diseases involved had not been complied with. Subclinical infections are a challenge for international trade: 88% of the regulated movements that resulted in introductions involved infected horses that showed no clinical signs at the time of import. Biosecurity and management practices in resident equine populations were identified as important mitigating factors in preventing disease spread to the local horse population. Conclusions: The global increase in international horse movements, if not appropriately regulated and supervised by competent veterinary authorities and respective equine industry partners, could potentially lead to increased global spread of infectious equine diseases. Appropriate mitigation measures and compliance with OIE import recommendations for specific diseases can significantly reduce this risk. The recommendations proposed under the HHP approach take into account the mitigation measures identified by this review as important factors in preventing pathogen introduction and spread.

54 Dunowska M. (2016) How common is equine herpesvirus type 1 infection? Vet Rec.;178(3):67-9. Abstract EQUINE herpesvirus type 1 (EHV-1) infection can be subclinical or lead to a number of clinical presentati-ons including abortions, neonatal death, respiratory disease or neurological disease. The apparent recent increase in the numbers of reported cases of equine herpesvirus myeloencephalopathy (EHM) in the USA and Europe (Kydd and others 2012) have caused concerns among veterinarians regarding possible transmission of EHV-1 among hospitalised horses, with the subsequent risk of nosocomial EHM cases. One of the key questions central to such concerns is ‘how common is it for hospitalised horses to shed EHV-1?’ According to the results of a paper by Pusterla and others (2015) summarised on page 70 of this issue of Veterinary Record, only 2.7 per cent of 4228 horses from 139 veterinary practices throughout the USA tested positive for EHV-1 DNA in their nasal secretions or blood. The strength of the study includes availability of a large data set from a wide geographical area, with sampling spanning a five-year period. While this relatively low EHV-1 detection rate may be reassuring to equine veterinarians, the data should be interpreted with consideration of the complexity of the relationship between EHV-1 and its equine host 55 Durand, B., et.al. Seroprevalence of West Nile and Usutu viruses in military working horses and dogs, Morocco, 2012: dog as an alternative WNV sentinel species? Epidemiol. Infect. (2016), 144, 1857–1864. Abstract A serosurvey of 349 military working horses and 231 military working dogs was conducted in ten sites in Morocco in 2012. This survey revealed a high level of exposure of these animals to flaviviruses: seroprevalence rates of 60% in horses and of 62% in dogs were observed using a competitive West Nile virus (WNV) enzyme- linked immunosorbent assay (cELISA). Seroneutralization test results showed that the majority of cELISA- positive results were due to exposure to WNV. Further assays conducted in vaccinated horses with a DIVA (Differentiating Infected from Vaccinated Animals) test indicated that anti-WNV antibodies had been stimulated through WNV natural infection. Moreover, in both species, seroneutralization tests suggested an exposure to Usutu virus (USUV). Data analysis did not show any significant difference of cELISA seropositivity risk between horses and dogs. Dogs may thus represent an interesting alternative to equines for the serological surveillance of WNV or USUV circulation, especially in areas where equine vaccination precludes passive surveillance (based on the detection of West Nile fever cases) in horses.

56 Durham, AE. (2016) Endocrine Disease in Aged Horses. Vet Clin North Am Equine Pract. ;32(2):301-15. Abstract Interest in both endocrine disease and geriatric health care has risen tremendously in recent years and is associated with a longer useful working life and an increasingly compassionate management approach with more retired horses being kept as companions. Pituitary pars intermedia dysfunction (PPID) is the best known and possibly the most common endocrinopathy in aged horses, although equine metabolic syndrome (EMS) is by no means uncommon. Indeed the 2 conditions may coexist. Consequently, discussion of PPID and EMS predominate in this article, with a little further discussion of rarer endocrinopathies.

57 Estell KE, et.al. (2016) Pneumonia Caused by Klebsiella spp. in 46 Horses. J Vet Intern Med. ,30(1):314-21. Abstract Background: Klebsiella spp. are implicated as a common cause of bacterial pneumonia in horses, but few reports describe clinical presentation and disease progression. Hypothesis/Objectives: To describe the signalment, clinicopathologic data, radiographic and ultrasonographic findings, antimicrobial susceptibility, outcome, and pathologic lesions associated with Klebsiella spp. pneumonia in horses. Animals: Forty-six horses from which Klebsiella spp. was isolated from the lower respiratory tract. Methods: Retrospective study. Medical records from 1993 to 2013 at the William R. Pritchard Veterinary Medical Teaching Hospital, University of California, Davis were reviewed. Exact logistic regression was performed to determine if any variables were associated with survival to hospital discharge. Results: Survival in horses <1 year old was 73%. Overall survival in adults was 63%. For adults in which Klebsiella pneumoniae was the primary isolate, survival was 52%. Mechanical ventilation preceded development of pneumonia in 11 horses. Complications occurred in 25/46 horses, with thrombophlebitis and laminitis occurring most frequently. Multi-drug resistance was found in 47% of bacterial isolates. Variables that significantly impacted survival included hemorrhagic nasal discharge, laminitis, and thoracic radiographs with a sharp demarcation between marked caudal pulmonary alveolar infiltration and more normal-appearing caudodorsal lung. Conclusions and Clinical Importance: Klebsiella spp. should be considered as a differential diagnosis for horses presenting with hemorrhagic pneumonia and for horses developing pneumonia after mechanical ventilation. Multi-drug resistance is common. Prognosis for survival generally is fair, but is guarded for adult horses in which K. pneumoniae is isolated as the primary organism.

58 Ekiri, AB, Long MT, Hernandez JA. (2016) Diagnostic performance and application of a real-time PCR assay for the detection of Salmonella in fecal samples collected from hospitalized horses with or without signs of gastrointestinal tract disease. Vet J.;208:28-32. Abstract The main objective of this study was to assess the diagnostic performance of a real-time polymerase chain reaction (PCR) assay for the detection of Salmonella in fecal samples collected from hospitalized horses with or without signs of gastrointestinal (GI) tract disease. The PCR assay used primers and a probe that targeted the invA gene of Salmonella. Assuming a sensitivity of 100% and a specificity of 96.6%, and a disease prevalence of 2%, 5%, and 10–15% in study horses, the PCR assay had a high (100%) negative predictive value, and a positive predictive value that ranged from 37% in horses without signs of GI disease that tested Salmonella culture-negative, to 60% in horses with signs of GI disease that tested Salmonella culturenegative, to 76–83% in horses with signs of GI disease that tested Salmonella culture-positive. This study provides evidence that the real-time PCR that targets the Salmonella invA gene can be used as a screening test for the detection of Salmonella in feces of hospitalized horses with signs of GI disease. Horses that test PCR-positive can be tested in series using bacteriologic culture to reduce false positive results or to provide additional data (e.g., antibiogram and serotyping data) that can be used to identify potential nosocomial Salmonella infections.

59 Fabiani JV, Lyons ET, Nielsen MK. (2016) Dynamics of Parascaris and Strongylus spp. parasites in untreated juvenile horses. Vet Parasitol; 230:62-66. Abstract Parasite control in foals is of utmost importance due to the high susceptibility to parasitic infection and disease in this age group. Foals are commonly co-infected with strongyle and ascarid parasites, which complicate parasite control strategies. The present study retrospectively investigated necropsy records of foals born into a university herd kept without anthelmintic treatment since 1979. The aims were to statistically analyze the relationship between fecal egg counts, worm burdens, foal age, sex, and season with specific focus on Parascaris and Strongylus spp. A total of 83 foals born between 1999 and 2015 were included. Foals were born between January and September within the given year and age at necropsy ranged between 27 and 563 days of age with a mean and median of 202 and 204 days, respectively. One set of multivariate mixed linear models was constructed analyzing strongyle and ascarid fecal egg counts as outcome variables, and another set of analyses investigated the following worm counts as outcome variables: Intestinal Parascaris spp. counts (immatures and adults), S. vulgaris (migrating and intestinal stages), S. edentatus (migrating and intestinal stages). Both ascarid and strongyle egg counts were influenced significantly by differences between study years (p < 0.05). In addition, total ascarid egg counts were statistically influenced by age (p = 0.020) exhibiting a peak at four months of age and fillies had significantly higher ascarid worm burdens (p = 0.043). Foal age had significant influences on intestinal counts of immature Parascaris spp. (p = 0.034) and adult S. edentatus counts (p = 0.028). Larval counts of S. edentatus were significantly associated with birth month (p = 0.023), whereas counts of migrating S. vulgaris larvae were not statistically associated with any of the investigated covariates. This study provides novel information on the dynamics of important parasites in naturally infected foals.

60 Ferreira, EP, et.al. (2016) Serological and molecular detection of Theileria equi in sport horses of northeastern Brazil. Comp Immunol Microbiol Infect Dis.;47:72-6. Abstract Theileriosis is a worldwide protozoal tick-borne disease caused by Theileria equi, which may produce avariety of clinical signs and turn infected horses into lifetime carriers. This study has aimed to performa serological and molecular detection of T. equi and associated factors in sports horses from six areasof northeastern Brazil. In overall, 59.6% horses were positive by indirect immunofluorescence assay and50.4% by polymerase chain reaction. No significant association was found when presence of ticks, age,gender, anemia or total plasma proteins was analyzed with seropositivity and molecular techniques.Although a significant association of infection was found in two cities. Thus, local risk factors other thanpresence of ticks, horse age, gender, anemia and total plasmatic proteins may dictate prevalence of T.equi infection in sports horses, even in highly endemic areas with no control of infection prior to horsecompetitions.

61 Frisbie, DD, et.al. (2016) Efficacy of intravenous administration of hyaluronan, sodium chondroitin sulfate, and N-acetyl-d-glucosamine for prevention or treatment of osteoarthritis in horses. Am J Vet Res.;77(10): 1064-70. Abstract The study involved 2 portions. To evaluate prophylactic efficacy of the test product, horses received 5 mL of the product (n = 8) or saline (0.9% NaCl) solution (8; placebo) IV every fifth day, starting on day 0 (when osteoarthritis was induced in the middle carpal joint of 1 forelimb) and ending on day 70. To evaluate treatment efficacy, horses received either the product or placebo (n = 8/treatment) on days 16, 23, 30, 37, and 44 after osteoarthritis induction. Clinical, diagnostic imaging, synovial fluid, gross anatomic, and histologic evaluations and other tests were performed. Results of each study portion were compared between treatment groups.

62 Guthrie, Amanda, et.al. (2016) Eastern equine encephalomyelitis virus infection in six captive southern cassowaries (Casuarius casuarius). JAVMA ,249 (3): 319-324 Abstract On July 17, 2014, a 27-day-old male cassowary (Casuarius casuarius) chick (case 1) was found weak and recumbent in its enclosure at a zoo in southeastern Virginia. The bird was manually restrained for physical examination and venipuncture. It subsequently developed abnormally increased respiratory effort and was weak and mentally obtunded. Whole-body radiographs were obtained and revealed a loss of serosal detail in the coelomic cavity and lungs with an abnormally decreased volume bilaterally and abnormally increased opacity, which was most prominent near the hilum.The chick was treated with midazolam (0.29 mg/kg [0.13 mg/lb], IM, once) as a prophylactic measure against the neurological signs that were anticipated. The chick also received ceftiofur hydrochloride (20 mg/kg [9 mg/lb], IM, once), furosemide (1.8 mg/kg [0.82 mg/lb], IM, once), enrofloxacin (5 mg/kg [2.27 mg/lb], IM, once), and isotonic saline (0.9% NaCl) solution (50 mL, SC) on the basis of treatment recommendations for critically ill exotic birds.1 A blood sample was obtained for a serum biochemical analysis and CBC. Clinicopathologic abnormalities included hyperuricemia (27.7 mg/dL; reference range,2 2.0 to 16.5 mg/dL), hypocalcemia (3.8 mg/dL; reference range,2 8.3 to 14.2 mg/dL), hyperphosphatemia (13.9 mg/dL; reference range,2 2.9 to 11.7 mg/dL), and abnormally high AST (3,379 U/L; reference range,2 243 to 811 U/L), GGT (121 U/L; reference value,2 27 U/L), and creatine kinase (2,538 U/L; reference range,2 192 to 1,246 U/L) activities. It is likely that amylase (6,479 U/L) and LDH (> 3,600 U/L) activities were also abnormally increased, but reference ranges for those enzymes in cassowaries have not been established. Microscopic examination of a blood smear revealed numerous heterophils with signs of marked acute toxicosis including cytoplasmic basophilia, moderate degranulation, and abnormal granules. All other CBC variables were within their respective reference ranges. Abnormalities identified during plasma elec- trophoresis included a low total protein concentration and low albumin-to-globulin ratio characterized by a mild to moderate increase in β globulins, which was indicative of an acute infection. The chick was kept in a warm incubator with oxygen supplementation and was found dead approximately 12 hours after the initial physical examination. 63 Hallamaa R, Batchu K. (2016) Phospholipid analysis in sera of horses with allergic dermatitis and in matched healthy controls. Lipids Health Dis.;15:45. Abstract Background: Lipids have become an important target for searching new biomarkers typical of different autoimmune and allergic diseases. The most common allergic dermatitis of the horse is related to stings of insects and is known as insect bite hypersensitivity (IBH) or summer eczema, referring to its recurrence during the summer months. This intense pruritus has certain similarities with atopic dermatitis of humans. The treatment of IBH is difficult and therefore new strategies for therapy are needed. Autoserum therapy based on the use of serum phospholipids has recently been introduced for horses. So far, serum lipids relating to these allergic disorders have been poorly determined. The main aim of this study was to analyse phospholipid profiles in the sera of horses with allergic dermatitis and in their healthy controls and to further assess whether these lipid profiles change according to the clinical status after therapy. Methods: Sera were collected from 10 horses with allergic dermatitis and from 10 matched healthy controls both before and 4 weeks after the therapy of the affected horses. Eczema horses were treated with an autogenous preparation made from a horse’s own serum and used for oral medication. Samples were analysed for their phospholipid content by liquid chromatography coupled to a triple-quadrupole mass spectrometer (LC-MS). Data of phospholipid concentrations between the groups and over the time were analysed by using the Friedman test. Correlations between the change of concentrations and the clinical status were assessed by Spearman’s rank correlation test. Results: The major phospholipid classes detected were phosphatidylcholine (PC), sphingomyelin (SM), phosphatidylinositol (PI) and phosphatidylethanolamine (PE). Eczema horses had significantly lower total concentrations of PC (p < 0.0001) and SM (p = 0.0115) than their healthy controls. After a 4-week therapy, no significant differences were found between the groups. Changes in SM concentrations correlated significantly with alterations in clinical signs (p = 0.0047). Conclusions: Horses with allergic dermatitis have an altered phospholipid profile in their sera as compared with healthy horses and these profiles seem to change according to their clinical status. Sphingomyelin seems to have an active role in the course of equine insect bite hypersensitivity.

64 Harris, PA, et.al. (2016) Review: Feeding conserved forage to horses: recent advances and recommendations. Animal. Nov 24:1-10. Abstract The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the proportion of the diet that is forage based. This may adversely affect the health, welfare, behaviour and even performance of the horse. In the past 20 years a large body of research work has contributed to a better and deeper understanding of equine forage needs and the physiological and behavioural consequences if these are not met. Recent nutrient requirement systems have incorporated some, but not all, of this new knowledge into their recommendations. This review paper amalgamates recommendations based on the latest understanding in forage feeding for horses, defining forage types and preservation methods, hygienic quality, feed intake behaviour, typical nutrient composition, digestion and digestibility as well as health and performance implications. Based on this, consensual applied recommendations for feeding preserved forages are provided. 65 Haspeslagh, M, et.al.(2016) Topical distribution of acyclovir in normal equine skin and equine sarcoids: An in vitro study. Res Vet Sci.;106:107-11. Abstract Topical acyclovir application is an owner-friendly treatment for occult equine sarcoids, without the caustic side-effects other topical treatments have. Variable clinical success rates have been described, but it is not known to what rate and extent acyclovir penetrates in and through equine skin from a topical formulation. In the current study, an in vitro Franz diffusion model was used to determine the permeation parameters for a generic 5% acyclovir cetomacrogol cream for both healthy and sarcoid equine skin. The distribution of acyclovir between different layers of both skin types was also evaluated. While acyclovir penetrated through both skin types, significantly less acyclovir permeated to the deep dermis of sarcoid skin (197.62 ng/mm³) compared to normal skin (459.41 ng/mm³). Within sarcoid skin samples, significantly higher acyclovir concentrations were found in the epidermis (983.59 ng/mm³) compared to the superficial dermis (450.02 ng/mm³) and the deep dermis. At each sample point, significantly more acyclovir permeated to the receptor fluid through normal skin compared to sarcoid skin, which is reflected in the significantly higher permeation parameters of normal skin. Normal skin was found to be more permissive for acyclovir, but even in sarcoid skin, enough acyclovir reached the deep dermis to treat a Herpes simplex virus infection. In the case of equine sarcoids, the treatment is aimed at the Bovine papillomavirus and no information is available on the susceptibility of the DNA polymerase of this virus for acyclovir. 66 Hernandez, D., et.al. (2016) Effects of various antiplatelet drugs on ex vivo platelet activation induced by equine herpesvirus type 1. Am J Vet Res. ;77(12):1366-1373. Abstract Equine herpesvirus type 1 is a highly contagious, double-stranded DNA virus associated with outbreaks of respiratory and neurologic disease, abortion, and neonatal death in horses. Infectious outbreaks cause severe economic losses to the racing industry and have a financial and emotional toll on owners of affected horses.1 When horses are infected with EHV-1, thrombi develop within various blood vessels, including those that supply the spinal cord and placenta.2–4 These thrombi are believed to contribute to the pathogenesis of the clinical syndromes of abortion and neurologic disease through ischemic injury.

67 Hitchens, PL, et.al. (2016) Prevalence and risk factors for overweight horses at premises in Sweden assessed using official animal welfare control data. Acta Vet Scand.; 58(Suppl 1): 61. Abstract Background: There are Swedish animal welfare regulations concerning the body condition of horses and general advice on keeping horses including that horses should be fed so that they do not become over- or underweight relative to their use. Compliance is assessed by official animal welfare inspectors. The objective of this study was to determine whether the national animal welfare control database could be used to estimate the prevalence and risk factors for overweight horses in Sweden. The official animal welfare control checklist for horses contains 45 checkpoints (CP) of which CP-8 pertains to the acceptability of the horses’ body condition including whether they were under- or overweight. Prevalence of non-compliance with CP-8, with 95 % confidence intervals (CI), were calculated for the years 2010–2013. Associations between risk factors and non- compliance for overweight body condition were estimated using logistic regression and expressed as odds ratios (OR) with 95 % CIs. Results: Of 7870 premises with registered horses that were inspected against CP-8, a total of 63 premises had noncompliant inspections due to overweight horses (0.80 %; CI 0.62, 1.02 %). In multivariable analyses, premises that were non-compliant with requirements for the care of sick or injured horses (OR 3.52; CI 1.51, 8.22) or with the requirements for feeding a balanced high-quality diet (OR 5.15; CI 2.49, 10.67) had greater odds of having overweight horses. Premises that also kept other species for meat production were more likely to have overweight horses (OR 2.12; CI 1.18, 3.81) whereas professional horse establishments were less likely (OR 0.09; 0.01, 0.64). Overweight horses were more likely in summer compared to winter (OR 2.18; CI 1.02, 4.70). Premises in regions of Sweden with more horses in relation to the human population were less likely to have overweight horses (OR 0.97; CI 0.95, 1.00). Conclusions: Official animal welfare control data may be used to monitor the premises prevalence of overweight horses in Sweden. Strategies to reduce the prevalence of overweight horses should focus on education about equine care and nutrition, especially summer grazing. Keywords: Epidemiology, Legislation, Compliance, Logistic regression, Horse, Body condition, Welfare, Welfare assessment, Equine, Obesity

68 Hlokwe, TM, Sutton D, Page P, Michel AL. (2016) Isolation and molecular characterization of Mycobacterium bovis causing pulmonary tuberculosis and epistaxis in a Thoroughbred horse. BMC Vet Res.;12(1):179. Abstract Background: Tuberculosis caused by Mycobacterium bovis (M. bovis) is very uncommon in horses worldwide. Case presentation: In the current study, an eight-year-old male Thoroughbred in good body condition was admitted to the Equine Clinic at the Onderstepoort Veterinary Academic Hospital in 2005 due to bilateral epistaxis accompanied by coughing. Routine examinations were conducted to determine the cause of the condition. Endoscopic examination revealed the major source of the epistaxis as the trachea, whereas thoracic radiography indicated the presence of a primary pulmonary mass. M. bovis was isolated from a broncho- alveolar lavage (BAL) sample collected. The pulmonary mass reduced in size three months later following an oral administration of enrofloxacin (7.5 mg/kg PO SID). Genetic fingerprinting by spoligotyping identified the M. bovis isolate as spoligotype SB0868 strain. This M. bovis strain type was never described previously in South Africa (SA). This is the first case of M. bovis infection in a horse in SA which has been fully documented including clinical findings, isolation and genetic characterisation of the causative pathogen. Conclusions: This report indicates that horses may contract and harbour M. bovis despite their lower susceptibility compared to other domestic animals. It also suggests that the infection may be more easily contained and eliminated from the host.

69 Hopster K,et.al. (2016) Histopathological changes and mRNA expression in lungs of horses after inhalation anaesthesia with different ventilation strategies. Res Vet Sci.;107:8-15. Abstract Inappropriate mechanical ventilation can lead to ventilator-induced lung injury (VILI). Aim of this study was to evaluate the effects of inhalation anaesthesia and ventilationwith andwithout recruitment (RM) and PEEP titration on alveolar integrity in horses.Twenty-three horses were divided into 4 groups (group OLC ventilated with OLC, group IPPV ventilated with intermittent positive pressure ventilation, group NV non-ventilated, and group C non-anaesthetized control group). After sedation with xylazine and induction with diazepam and ketamine anaesthetized horses were under isoflurane anaesthesia for 5.5 h. The horses were euthanized and tissue samples of the dependent and nondependent lung areas were collected. Histopathological examinations of the lung tissue as well as relative quantification of mRNA of IL-1β, IL-6, iNOS, MMP1 and MMP9 by PCR were performed. Horses of group OLC had significantly less alveolar congestion and atelectasis but greater alveolar overdistension compared to groups NV and IPPV. In groups OLC and group IPPV an increase in IL- 1β/6 andMMP1/9was detected compared to groups NV and C. In conclusion, in breathing spontaneously or IPPV-ventilated horses a higher degree of atelectasis was detected, whereas in OLC-ventilated horses a higher degree of overdistention was present. Elevated levels in IL and MMP might be early signs of VILI in ventilated horses.

70 Humblet, MF, et.al. (2016) Estimating the economic impact of a possible equine and human epidemic of West Nile virus infection in Belgium. Euro Surveill.;21(31) Abstract This study aimed at estimating, in a prospective scenario, the potential economic impact of a possible epidemic of WNV infection in Belgium, based on 2012 values for the equine and human health sectors, in order to increase preparedness and help decision-makers. Modelling of risk areas, based on the habitat suitable for Culex pipiens, the main vector of the virus, allowed us to determine equine and human populations at risk. Characteristics of the different clinical forms of the disease based on past epidemics in Europe allowed morbidity among horses and humans to be estimated. The main costs for the equine sector were vaccination and replacement value of dead or euthanised horses. The choice of the vaccination strategy would have important consequences in terms of cost. Vaccination of the country's whole population of horses, based on a worst-case scenario, would cost more than EUR 30 million; for areas at risk, the cost would be around EUR 16- 17 million. Regarding the impact on human health, short-term costs and socio-economic losses were estimated for patients who developed the neuroinvasive form of the disease, as no vaccine is available yet for humans. Hospital charges of around EUR 3,600 for a case of West Nile neuroinvasive disease and EUR 4,500 for a case of acute flaccid paralysis would be the major financial consequence of an epidemic of West Nile virus infection in humans in Belgium

71 Isani, G, et.al. (2016) Identification of the most abundant proteins in equine amniotic fluid by a proteomic approach. Anim Reprod Sci.;174: 150-160. Abstract Characterisation of the physiologic equine amniotic fluid (AF) proteome is a prerequisiteto study its changes during diseases and discover new biomarkers. The aim of this studywas to identify by a proteomic approach the most abundant proteins of equine AF. AFsamples were collected at parturition from 24 healthy mares that delivered healthy foals.All samples were subjected to sodium dodecyl sulphate polyacrylamide gel electrophore-sis (SDS-PAGE) on 4–12% gels. A pool of the 24 samples, after SDS-PAGE, was cut in 25slices, trypsin-digested and analysed by mass spectrometry (MS) for protein identification.Mean AF protein concentration was 1.96 ± 1.12 g/L. Thirty-four proteins were successfullyidentified by MS and subsequently categorised according to Gene Ontology (GO). Twelveproteins (e.g. fibronectin, lumican, thrombospondin and fibulin) belonged to or interactedwith the extracellular matrix (ECM) playing an important role in the development of foetaltissues. Most of the remaining proteins were classified as transport (e.g. albumin, majorallergen Equ c1 and alpha-fetoprotein) delivering nutrients, ions and lipids essential forfoetal growth and development. Among these proteins, major allergen Equ c1 is widelystudied in human medicine because it induces Ig-E mediated type I allergic reaction. Theabsence of immunoglobulins in equine AF was also confirmed.

72 Kim, SK, et.al. (2016) Full trans-activation mediated by the immediate-early protein of equine herpesvirus 1 requires a consensus TATA box, but not its cognate binding sequence. Virus Res.;211:222-32. Abstract The immediate-early protein (IEP) of equine herpesvirus 1 (EHV-1) has extensive homology to the IEPof alphaherpesviruses and possesses domains essential for trans-activation, including an acidic trans-activation domain (TAD) and binding domains for DNA, TFIIB, and TBP. Our data showed that the IEPdirectly interacted with transcription factor TFIIA, which is known to stabilize the binding of TBP andTFIID to the TATA box of core promoters. When the TATA box of the EICP0 promoter was mutated toa nonfunctional TATA box, IEP-mediated trans-activation was reduced from 22-fold to 7-fold. The IEPtrans-activated the viral promoters in a TATA motif-dependent manner. Our previous data showed thatthe IEP is able to repress its own promoter when the IEP-binding sequence (IEBS) is located within 26-bp from the TATA box. When the IEBS was located at 100 bp upstream of the TATA box, IEP-mediatedtrans-activation was very similar to that of the minimal IE(nt −89 to +73) promoter lacking the IEBS.As the distance from the IEBS to the TATA box decreased, IEP-mediated trans-activation progressivelydecreased, indicating that the IEBS located within 100 bp from the TATA box sequence functions as adistance-dependent repressive element. These results indicated that IEP-mediated full trans-activationrequires a consensus TATA box of core promoters, but not its binding to the cognate sequence (IEBS).

73 Kinsley R, Scott SD, Daly JM. (2016) Controlling equine influenza: Traditional to next generation serological assays. Vet Microbiol.;187:15-20. Abstract Serological assays provide an indirect route for the recognition of infectious agents via the detection of antibodies against the infectious agent of interest within serum. Serological assays for equine influenza A virus can be applied for different purposes: diagnosing infections; subtyping isolates; surveillance of circulating strains; and to evaluate the efficacy of vaccines before they reach the market. Haemagglutination inhibition (HI) and single radial haemolysis (SRH) assays are most commonly used in the equine field. This review outlines how both these assays together with virus neutralization (VN) and ELISA are performed, interpreted and applied for the control of equine influenza, giving the limitations and advantages of each. The pseudotyped virus neutralization assay (PVNA) is also discussed as a promising prospect for the future of equine influenza virus serology.

74 Knottenbelt DC. (2016) Integumentary Disorders Including Cutaneous Neoplasia in Older Horses. Vet Clin North Am Equine Pract.;32(2):263-81. Abstract The skin of the horse is a highly visible and accessible organ that can reflect the overall health status of the horse or be affected by primary or secondary diseases. In a disease survey of 200 geriatric horses (_15 years of age) 71% had a dermatologic abnormality and 22% displayed hirsutism or abnormal shedding. Although the dermatologic abnormalities were not specifically identified/diagnosed, many were secondary bacterial, fungal, and parasitic infections (possibly related to degrees of immunocompromise) or neoplastic.1 A recent pathologic study showed that in 4.2% the causes of death or euthanasia of animals more than 15 years of age were attributable to skin disease, including sarcoid, melanoma, lymphoma, and squamous cell carcinoma, and most of these were cutaneous

75 Kumar, N, Bera BC,et.al. (2016) Revelation of Influencing Factors in Overall Codon Usage Bias of Equine Influenza Viruses. PLoS One.;11(4):e0154376.

Abstract Equine influenza viruses (EIVs) of H3N8 subtype are culprits of severe acute respiratory infections in horses, and are still responsible for significant outbreaks worldwide. Adaptability of influenza viruses to a particular host is significantly influenced by their codon usage preference, due to an absolute dependence on the host cellular machinery for their replication. In the present study, we analyzed genome-wide codon usage patterns in 92 EIV strains, including both H3N8 and H7N7 subtypes by computing several codon usage indices and applying multivariate statistical methods. Relative synonymous codon usage (RSCU) analysis disclosed bias of preferred synonymous codons towards A/U-ended codons. The overall codon usage bias in EIVs was slightly lower, and mainly affected by the nucleotide compositional constraints as inferred from the RSCU and effective number of codon (ENc) analysis. Our data suggested that codon usage pattern in EIVs is governed by the interplay of mutation pressure, natural selection from its hosts and undefined factors. The H7N7 subtype was found less fit to its host (horse) in comparison to H3N8, by possessing higher codon bias, lower mutation pressure and much less adaptation to tRNA pool of equine cells. To the best of our knowledge, this is the first report describing the codon usage analysis of the complete genomes of EIVs. The outcome of our study is likely to enhance our understanding of factors involved in viral adaptation, evolution, and fitness towards their hosts.

76 Kwasnik M, Gora IM, Rola J, Zmudzinski JF, Rozek W. (2016) NS-gene based phylogenetic analysis of equine influenza viruses isolated in Poland. Vet Microbiol.;182:95-101. Abstract The phylogenetic analysis of influenza virus is based mainly on the variable hemagglutinin or neuraminidase genes. However, some discrete evolutionary trends might be revealed when more conservative genes are considered. We compared all available in GenBank database full length NS sequences of equine influenza virus including Polish isolates. Four nucleotides at positions A202, A237, T672 and A714 and three amino acids at positions H59, K71 and S216 which are also present in A/eq/Pulawy/2006 and A/eq/Pulawy/2008 may be discriminating for the Florida sublineage. Threonine at position 83 seems to be characteristic for EIV strains of Florida 2 isolated after 2007. There are nine common substitutions in the NS sequences of A/eq/ Pulawy/2005, A/eq/Aboyne/1/2005 and A/eq/Lincolnshire/1/2006 in relation to the reference strain A/eq/ Miami/63, resulting in four amino acid changes in NS1 protein (I56, E76, K140, E179) and one in NEP (R22). We grouped these strains as “Aboyne-like”. Some of the listed changes were also observed in H7N7 strains isolated between 1956 and 1966, in A/eq/Jilin/89 or in pre-divergent H3N8 strains. Two hypotheses regarding the origin of this group were postulated: three independent transfers of avian influenza viruses into the equine population or reassortation between H7N7 and H3N8 EIV. Similarities of the NS sequences of “Aboyne like” viruses to viruses isolated in the fifties or seventies can reflect a phenomenon of “frozen evolution”.

77 de Laat MA, McGree JM, Sillence MN. (2016) Equine hyperinsulinemia: investigation of the enteroinsular axis during insulin dysregulation. Am J Physiol Endocrinol Metab.;310(1):E61-72. Abstract Equine hyperinsulinemia: investigation of the enteroinsular axis during insulin dysregulation. Am J Physiol Endocrinol Metab 310: E61–E72, 2016. First published November 3, 2015; doi:10.1152/ajpendo. 00362. 2015.— Compared with some other species, insulin dysregulation in equids is poorly understood. However, hyperinsulinemia causes laminitis, a significant and often lethal disease affecting the pedal bone/hoof wall attachment site. Until recently, hyperinsulinemia has been considered a counterregulatory response to insulin resistance (IR), but there is growing evidence to support a gastrointestinal etiology. Incretin hormones released from the proximal intestine, glucagon-like peptide- 1 (GLP-1) and glucose-dependent insulinotropic peptide, augment insulin secretion in several species but require investigation in horses. This study investigated peripheral and gut-derived factors impacting insulin secretion by comparing the response to intravenous (iv) and oral D-glucose. Oral and iv tests were performed in 22 ponies previously shown to be insulin dysregulated, of which only 15 were classified as IR (iv test). In a more detailed study, nine different ponies received four treatments: D-glucose orally, D-glucose iv, oats, and commercial grain mix. Insulin, glucose, and incretin concentrations were measured before and after each treatment. All nine ponies showed similar iv responses, but five were markedly hyperresponsive to oral D-glucose and four were not. Insulin responsiveness to oral D- glucose was strongly associated with blood glucose concentrations and oral glucose bioavailability, presumably driven by glucose absorption/ distribution, as there was no difference in glucose clearance rates. Insulin was also positively associated with the active amide of GLP-1 following D-glucose and grain. This study has confirmed a functional enteroinsular axis in ponies that likely contributes to insulin dysregulation that may predispose them to laminitis. Moreover, iv tests for IR are not reliable predictors of the oral response to dietary nonstructural carbohydrate.

78 Laskoski LM, et.al. (2016) Oxidative stress in hoof laminar tissue of horses with lethal gastrointestinal diseases. Vet Immunol Immunopathol.;171:66-72. Abstract Tissue damage caused by oxidative stress is involved in the pathogenesis of several diseases in ani-mals and man, and is believed to play a role in the development of laminitis in horses. The aim of thisstudy was to investigate the oxidative stress associated with laminar lesions in horses with lethal gas-trointestinal disorders. Laminar tissue samples of the hoof of 30 horses were used. Tissue samples weredivided as follows: six healthy horses (control group—CG), and 24 horses that died after complications ofgastrointestinal diseases (group suffering from gastrointestinal disorders—GDG). Superoxide dismutase(SOD2) and nitrotyrosine immunostaining and the severity of laminar lesions were evaluated. Presenceof laminar lesions and immunostaining for nitrotyrosine and SOD2 were only evident in horses from theGDG group. Thus, oxidative stress may play a role in the pathogenesis of laminar lesions secondary togastrointestinal disorders 79 Libardoni F,et.al. (2016) Prevalence of Streptococcus equi subsp. equi in horses and associated risk factors in the State of Rio Grande do Sul, Brazil. Res.Vet Sci.;104:53-7. Abstract The aim of this study was to estimate the prevalence of equine strangles and to identify associated risk factors for this disease through a cross-sectional study of nasal swabs. Nasal swabs (n= 1010) from healthy equines (absence of nasal discharge, lymphadenopathy and cough) from 341 farms were plated on 5% blood agar; of these horses, 24 were identified as positive for Streptococcus equi through isolation, PCR and DNA sequencing. The estimated prevalence for individual animals was 2.3%, and for herds, it was 5.86%. Statistical analysis identified the following as associated risk factors: the number of group events thatwere attended by the equines (PR: 1.06); the sharing of food containers (PR: 3.74); and at least one previous positive diagnosis of strangles on the farm (PR:3.20). These results constitute an epidemiological contribution to the horse industry and may support measures for the future control of the disease.

80 Liu, Q, Meli ML, et.al. (2016) Sequence heterogeneity in the 18S rRNA gene in Theileria equi from horses presented in Switzerland. Vet Parasitol.;221:24-9. Abstract A reverse line blot (RLB) hybridization assay was adapted and applied for equine blood samples collected at the animal hospital of the University of Zurich to determine the presence of piroplasms in horses in Switzerland. A total of 100 equine blood samples were included in the study. The V4 hypervariable region of the 18S rRNA gene was amplified by polymerase chain reaction and analyzed using the RLB assay. Samples from seven horses hybridized to a Theileria/Babesia genus-specific and a Theileria genus-specific probe. Of these, two hybridized also to the Theileria equi-specific probe. The other five positive samples did not hybridize to any of the species-specific probes, suggesting the presence of unrecognized Theileria variants or genotypes. The 18S rRNA gene of the latter five samples were sequenced and found to be closely related to T. equi isolated from horses in Spain (AY534822) and China (KF559357) (≥98.4% identity). Four of the seven horses that tested positive had a documented travel history (France, Italy, and Spain) or lived abroad (Hungary). The present study adds new insight into the presence and sequence heterogeneity of T. equi in Switzerland. The results prompt that species-specific probes must be designed in regions of the gene unique to T. equi. Of note, none of the seven positive horses were suspected of having Theileria infection at the time of presentation to the clinic. Clinicians should be aware of the possibility of equine piroplasma infections outside of endemic areas and in horses without signs of piroplasmosis.

81 Liu, Q, Ma J,et.al. (2016) Infection with equine infectious anemia virus vaccine strain EIAVDLV121 causes no visible histopathological lesions in target organs in association with restricted viral replication and unique cytokine response. Vet Immunol Immunopathol.;170:30-40. Abstract The liveequineinfectiousanemiavirus(EIAV)vaccinestrainEIAVDLV121 was developedby in vitro atten-uation ofavirulentstrain,EIAVLN40, inthe1970s,andithasbeendemonstratedtoinduceprotective immunity under laboratoryandnaturalEIAVinfectionconditions.Thedetailedbiologicalfeaturesofthis attenuated virus remain tobe further investigated.ExperimentalinoculationwithEIAVDLV121 did not result in clinical symptomseven with immunosuppressive treatment inourprevious studies.Here,we further investigated whetherthe replication of the vaccine strain EIAVDLV121 in experimentallyinfected horses caused histopathological lesionstodevelopinthe targeted organs.Boththelungsand thespleen have beendemonstrated to support EIAVreplication. By evaluating the grossmacroscopic and histological changes,wefound that EIAVDLV121 did not cause detectable histopathological lesions and thatitreplicated several hundred timesmoreslowlythanitsparental virulent strain, EIAVLN40, intissues.Immunochemical assays of the setissues indicatedthattheprimarytargetcellsofEIAVDLV121 were monocytes/macrophages, but that EIAVLN40 also infected alveolarepithelial cells and vascular endothelialcells. Inaddition,both of the seviral strains promoted the up-anddown-regulation of the expression of various cytokines and chemokines, implicating the potentialinvolvement of these cellular factors in the pathological outcomes of EIAVinfection and hostimmuneresponses. Takentogether, these resultsdemonstrate that theEIAV vaccine strain doesnot cause obvioushisto pathological lesions or clinical symptom sand that itinduces a uniquecytokineresponse profile.ThesefeaturesareconsideredessentialforEIAVDLV121 to functionas an effectivelivevaccine.

82 Liu, SH, Li K, Hu DF. The incidence and species composition of Gasterophilus (Diptera, Gasterophilidae) causing equine myiasis in northern Xinjiang, China. Vet Parasitol. 2016;217:36-8. Abstract A survey was conducted on the detection of the larval Gasterophilus species in 90 equines via necropsy or after administering oral ivermectin in Xinjian, China, from 2008 to 2013. All 90 (100%) equines were infested by larval Gasterophilus, and 3723 second instar larvae (L2) and 63,778 third instar larvae (L3) were collected from faecal samples and the digestive tract, a ratio of L2:L3 = 1:17. Over 84.45% of the animals contained ≤1500 larvae and 7.78% had >2000 larvae. The highest totals of L2 and L 3 larvae in any one animal were 1208 in Mongolian wild ass (Equus hemionus hemionus), 2491 in Przewalski’s horse (Equus ferus przewalskii), and 1785 in the domestic horse (Equus ferus caballus). Six species of Gasterophilus were identified, with the following proportions of overall parasite abundance: Gasterophilus pecorum 88.94%, Gasterophilus nigricornis 4.94%, Gasterophilus nasalis 3.93%, Gasterophilus haemorrhoidalis 1.91%, Gasterophilus intestinalis 0.19%, and Gasterophilus inermis 0.087%. A majority of equines (n = 32, 35.57%) was infested with five Gasterophilus species, while 29 animals (32.22%) harboured four species, 13 animals (14.44%) had six, 12 animals (13.33%) had three, three (3.33%) had two, and one (1.11%) had only one species. The percentage of Przewalski’s horses infested was higher than local domestic horse or Mongolian wild ass.

83 Lu, G, He D, Wang Z, Ou S, Yuan R, Li S. (2016) Cloning the Horse RNA Polymerase I Promoter and Its Application to Studying Influenza Virus Polymerase Activity. Viruses.; 8(6). pii: E119.

Abstract An influenza virus polymerase reconstitution assay based on the human, dog, or chicken RNA polymerase I (PolI) promoter has been developed and widely used to study the polymerase activity of the influenza virus in corresponding cell types. Although it is an important member of the influenza virus family and has been known for sixty years, no studies have been performed to clone the horse PolI promoter or to study the polymerase activity of equine influenza virus (EIV) in horse cells. In our study, the horse RNA PolI promoter was cloned from fetal equine lung cells. Using the luciferase assay, it was found that a 500 bp horse RNA PolI promoter sequence was required for efficient transcription. Then, using the developed polymerase reconstitution assay based on the horse RNA PolI promoter, the polymerase activity of two EIV strains was compared, and equine myxovirus resistance A protein was identified as having the inhibiting EIV polymerase activity function in horse cells. Our study enriches our knowledge of the RNA PolI promoter of eukaryotic species and provides a useful tool for the study of influenza virus polymerase activity in horse cells. 84 Lu Zhengchun, et.al. Conserved arginine residues in the carboxyl terminus of the equine arteritis virus E protein may play a role in heparin binding but may not affect viral infectivity in equine endothelial cells.- Arch Virol (2016) 161:873–886. Abstract Equine arteritis virus (EAV), the causative agent of equine viral arteritis, has relatively broad cell tropism in vitro. In horses, EAV primarily replicates in macrophages and endothelial cells of small blood vessels. Until now, neither the cellular receptor(s) nor the mechanism(s) of virus attachment and entry have been determined for this virus. In this study, we investigated the effect of heparin on EAV infection in equine endothelial cells (EECs). Heparin, but not other glycosaminoglycans, could reduce EAV infection up to 93 %. Sequence analysis of the EAV E minor envelope protein revealed a conserved amino acid sequence (52RSLVARCSRGARYR65) at the carboxy terminus of the E protein, which was predicted to be the heparin-binding domain. The basic arginine (R) amino acid residues were subsequently mutated to glycine by site-directed mutagenesis of ORF2a in an E protein expression vector and an infectious cDNA clone of EAV. Two single mutations in E (R52G and R57G) did not affect the heparin-binding capability, whereas the E double mutation (R52,60G) completely eliminated the interaction between the E protein and heparin. Although the mutant R52,60G EAV did not bind heparin, the mutations did not completely abolish infectivity, indicating that heparin is not the only critical factor for EAV infection. This also suggested that other viral envelope protein(s) might be involved in attachment through heparin or other cell-surface molecules, and this warrants further investigation.

85 Machteld, C. Van Dierendonck, Johannes P.A.M. van Loon (2016) Monitoring acute equine visceral pain with the Equine Utrecht University Scale for Composite Pain Assessment (EQUUS-COMPASS) and the Equine Utrecht University Scale for Facial Assessment of Pain (EQUUS-FAP): A validation study. The Veterinary Journal 216 175–177. Abstract This study presents the validation of two recently described pain scales, the Equine Utrecht University Scale for Composite Pain Assessment (EQUUS-COMPASS) and the Equine Utrecht University Scale for Facial Assessment of Pain (EQUUS-FAP), in horses with acute colic. A follow-up cohort study of 46 adult horses (n = 23 with acute colic; n = 23 healthy control horses) was performed for validation and refinement of the constructed scales. Both pain scales showed statistically significant differences between horses with colic and healthy control horses, and between horses with colic that could be treated conservatively and those that required surgical treatment or were euthanased. Sensitivity and specificity were good for both EQUUS- COMPASS (87% and 71%, respectively) and EQUUS-FAP (77% and 100%, respectively) and were not substantially influenced by applying weighting factors to the individual parameters.

86 Madrigal, R.G., et.al. (2016) Use of Serial Quantitative PCR of the vapA Gene of Rhodococcus equi in Feces for Early Detection of R. equi Pneumonia in Foals. J Vet Intern Med;30:664–670 Abstract Background: Current screening tests for Rhodococcus equi pneumonia in foals lack adequate accuracy for clinical use. Real-time, quantitative PCR (qPCR) for virulent R. equi in feces has not been systematically evaluated as a screening test. Objective: The objective of this study was to evaluate the accuracy of qPCR for vapA in serially collected fecal samples as a screening test for R. equi pneumonia in foals. Animals: One hundred and twenty-five foals born in 2011 at a ranch in Texas. Methods: Fecal samples were collected concurrently with thoracic ultrasonography (TUS) screening examinations at ages 3, 5, and 7 weeks. Affected (pneumonic) foals (n = 25) were matched by age and date-of-birth to unaffected (n = 25) and subclinical (ie, having thoracic TUS lesions but no clinical signs of pneumonia) foals (n = 75). DNA was extracted from feces using commercial kits and concentration of virulent R. equi in feces was determined by qPCR. Results: Subsequently affected foals had significantly greater concentrations of vapA in feces than foals that did not develop pneumonia (unaffected and subclinical foals) at 5 and 7 weeks of age. Accuracy of fecal qPCR, however, was poor as a screening test to differentiate foals that would develop clinical signs of pneumonia from those that would remain free of clinical signs (including foals with subclinical pulmonary lesions attributed to R. equi) using receiver operating characteristic (ROC) methods. Conclusions and Clinical Importance: In the population studied, serial qPCR on feces lacked adequate accuracy as a screening test for clinical R. equi foal pneumonia

87 Mahmoud, MS,et.al. (2016) Assessment of Theileria equi and Babesia caballi infections in equine populations in Egypt by molecular, serological and hematological approaches. Parasit Vectors.;9:260. Abstract Background: Equine piroplasmosis (EP) caused by Theileria equi, Babesia caballi, or both, contributes to significant economic loss in the equine industry and remains uncontrolled in Egypt. This study focuses on surveying T. Equi and B. caballi infections and hematological disorders in equine populations in Egypt. Methods: Theileria equi and B. caballi infections were assessed in blood from 88 horses and 51 donkeys in Egypt using light microscopy, indirect immunofluorescent antibody test (IFAT), nested PCR (nPCR), and competitive-ELISA (cELISA) assays. PCR products were examined for specificity by DNA sequencing. Hematological alterations were evaluated using a standard cell counter. Results: Microscopic analysis revealed EP infection in 11.4 % and 17.8 % of horses and donkeys respectively. IFAT detected 23.9 % and 17.0 % infection of T. equi and B. caballi, respectively, in horses, and 31.4 % of T. equi and B. caballi in donkeys. T. equi cELISA detected 14.8 % and 23.5 % positive horses and donkeys, respectively, but the B. caballi RAP-1- based cELISA failed to detect any positives, a result hypothesized to be caused by sequence polymorphism found in the rap-1 genes. Nested-PCR analysis identified 36.4 % and 43.1 % positive horses and donkeys, respectively for T. equi and it also identified 19.3 % and 15.7 % positive horses and donkeys, respectively for B. caballi. The overall EP incidence found in the population under study was relatively high and comparable regardless of the diagnostic method used (56.8 % using nPCR and 48.9 % using IFAT). Hematologic analysis revealed macrocytic hypochromic anemia and thrombocytopenia in all piroplasma-infected horses. Conclusions: The data confirm relatively high levels of EP, likely causing hematological abnormalities in equines in Egypt, and also suggest the need for an improved serological test to diagnose B. caballi infection in this region

88 Malalana, F. (2016) Ophthalmologic Disorders in Aged Horses. Vet Clin North Am Equine Pract.;32(2):249-61. Abstract Ocular abnormalities are common in aged horses. Superficial nonhealing corneal ulcers seem more prevalent in older horses, perhaps as a result of decreased corneal sensitivity. Significant ocular disorder as a result of recurrent uveitis can manifest more clearly as horses age. Important consequences of recurrent uveitis are cataracts and glaucoma. Several retinal and vitreal abnormalities are commonly seen in old horses, with variable effects on vision.

89 Marr, CM. (2016) Cardiac and Respiratory Disease in Aged Horses. Vet Clin North Am Equine Pract.;32(2):283-300. Abstract Respiratory and cardiac disease are common in older horses. Advancing age is a specific risk factor for cardiac disease. Recurrent airway obstruction can lead to irreversible structural change and bronchiectasis and, with chronic hypoxia, right heart dysfunction and failure can develop. Valvular heart disease often affects the aortic and/or the mitral valve; it does not necessarily shorten life span, but can progress to congestive heart failure. Management of comorbidity is an essential element of the therapeutic approach to cardiac and respiratory disease in older equids.

90 Marycz K, et.al. Equine Metabolic Syndrome Affects Viability, (2016) Senescence, and Stress Factors of Equine Adipose-Derived Mesenchymal Stromal Stem Cells: New Insight into EqASCs Isolated from EMS Horses in the Context of Their Aging. Oxid Med Cell Longev.;2016:4710326. Abstract Currently, equine metabolic syndrome (EMS), an endocrine disease linked to insulin resistance, affects an increasing number of horses. However, little is known about the effect of EMS on mesenchymal stem cells that reside in adipose tissue (ASC). Thus it is crucial to evaluate the viability and growth kinetics of these cells, particularly in terms of their application in regenerative medicine. In this study, we investigated the proliferative capacity, morphological features, and accumulation of oxidative stress factors in mesenchymal stem cells isolated from healthy animals (ASCN) and horses suffering from EMS (ASCEMS). ASCEMS displayed senescent phenotype associated with 훽-galactosidase accumulation, enlarged cell bodies and nuclei, increased apoptosis, and reduced heterochromatin architecture. Moreover, we observed increased amounts of nitric oxide (NO) and reactive oxygen species (ROS) in these cells, accompanied by reduced superoxide dismutase (SOD) activity.We also found in ASCEMS an elevated number of impaired mitochondria, characterized by membrane raptures, disarrayed cristae, and vacuole formation. Our results suggest that the toxic compounds, accumulating in the mitochondria under oxidative stress, lead to alternations in theirmorphology and may be partially responsible for the senescent phenotype and decreased proliferation potential of ASCEMS

91 Masatani T, Takashima Y, Takasu M, Matsuu A, Amaya T. (2016) Prevalence of anti-Toxoplasma gondii antibody in domestic horses in Japan. Parasitol Int.;65(2):146-50. Abstract The present study is the first report that investigated the seroprevalence of Toxoplasma gondii infection in domestic horses in various prefectures of Japan and analyzed risk factors for seropositivity. We performed a latex agglutination test for riding/racing horses from 11 prefectures in Japan (783 samples) and 4 groups of Japanese native horses (254 samples). The total seroprevalence of anti-T. gondii antibody in horses examined in this study was 4.24% (44/1037). As for riding/racing horses, we did not find a statistically different T. Gondii seroprevalence between sampling prefectures. In contrast, seroprevalence of T. gondii in older horses (N21 years) was significantly higher than that in younger horses (b5 years and 11–15 years). There was no significant difference in T. gondii seroprevalence between riding/racing horses and Japanese native horses. Logistical regression analysis revealed that age, but not sex and usage, is a significant risk factor of T. gondii infection for domestic horses in Japan. These findings suggest that domesticated horses in Japan can be horizontally infected with T. gondii by ingestion of food or water contaminated with oocysts

92 McFadden AM, et.al. (2016) The first reported outbreak of equine herpesvirus myeloencephalopathy in New Zealand. N Z Vet J.;64(2):125-34. Abstract CASE HISTORY AND CLINICAL FINDINGS: On 9 January 2014 (Day 0) a mare from a stud farm in the Waikato region presented with urinary incontinence without pyrexia. Over the following 33 days 15 mares were clinically affected with neurological signs. All but one mare had a foal at foot. The most commonly observed clinical signs were hind limb paresis and ataxia. In some cases recumbency occurred very early in the course of disease and seven mares were subject to euthanasia for humane reasons. LABORATORY FINDINGS: Equid herpesvirus (EHV) type 1 was detected using PCR in various tissues collected post mortem from two mares with neurological signs. DNA sequencing data from the DNA polymerase gene of the virus showed a nucleotide transition at position 2254, a mutation encoding amino acid D752 that is highly associated with the neuropathogenic genotype of EHV-1. In total 12/15 mares were confirmed positive for EHV-1 on PCR. Results from a virus neutralisation test and ELISA on paired serum samples, and PCR on whole blood and nasal swabs, indicated that of four paddocks in a high-risk area where a cluster of cases had occurred, 20/21 (95%) horses were likely to have been exposed or were confirmed infected with EHV-1. Subsequent to the outbreak two mares aborted, one at 9 months and one at 10 months of gestation. The cause of abortion was confirmed as EHV-1 with the same genotype as that involved in the outbreak. DIAGNOSIS: Equine herpesvirus myeloencephalopathy. CLINICAL RELEVANCE: The outbreak described shows the considerable impact that can occur in outbreaks of equine herpesvirus myeloencephalopathy in New Zealand. Early biosecurity controls not only reduced the effect on the farm but mitigated the potential for the virus to spread to other horse enterprises.

93 McQueen, Cole M. (2016)TRPM2 SNP genotype previously associated with susceptibility to Rhodococcus equi pneumonia in Quarter Horse foals displays differential gene expression identified using RNA-Seq. BMC Genomics ,17:993 Abstract Background: Rhodococcus equi (R. equi) is an intracellular bacterium that affects young foals and immuno- compromised individuals causing severe pneumonia. Currently, the genetic mechanisms that confer susceptibility and/or resistance to R. equi are not fully understood. Previously, using a SNP-based genome- wide association study, we identified a region on equine chromosome 26 associated with culture-confirmed clinical pneumonia. To better characterize this region and understand the function of the SNP located within TRPM2 that was associated with R. equi pneumonia, we performed RNA-Seq on 12 horses representing the 3 genotypic forms of this SNP. Results: We identified differentially expressed genes in the innate immune response pathway when comparing homozygous A allele horses with the AB and BB horses. Isoform analyses of the RNA-Seq data predicted the existence of multiple transcripts and provided evidence of differential expression at the TRPM2 locus. This finding is consistent with previously demonstrated work in human cell lines in which isoform-specific expression of TRPM2 was critical for cell viability. Conclusions: This work demonstrates that SNPs in TRPM2 are associated with differences in gene expression, suggesting that modulation of expression of this innate immune gene contributes to susceptibility to R. equi pneumonia.

94 Kale Mehmet, et.al.Serological Investigation of West Nile Virus Infection in Domestic Horses and Donkeys in Turkey. Pak Vet J, 37(1): 51-54

Abstract West Nile Virus (WNV) antibody presence was studied in domestic horse (Equus caballus) and donkeys (Equus asinus) of various age and types owned by public in different regions of Turkey. In the study, serum samples were collected from 650 domestic horses and 234 domestic donkeys seeming to be in good health. In order to detect WNV antibody presence in these samples, commercial c-ELISA (Competitive Enzyme Linked Immunosorbent Assay) kit (ID Screen® West Nile Competition-IgG- ELISA kit, Montpellier, France) was used. At the end of the test, WNV seropositivity was detected at a level of 4.15% (27/650) for horse serum samples and 1.28% (3/234) for donkey serum samples. Seropositivity was found for horses in Aegean and Central Anatolia and for donkeys in Eastern Anatolia regions. WNV seropositivity was detected only for Native Anatolia type horse races. It was concluded that WNV presence continued its existence among equidae in our country

95 Mentoor, Juliet L. D., et.al. (2016) Full-Genome Sequence of a Neuroinvasive West Nile Virus Lineage 2 Strain from a Fatal Horse Infection in South Africa. Genome Announ, 4: e00740-16 Abstract We report here the complete genome sequence of a lineage 2 West Nile virus (WNV) strain that resulted in fatal neurological disease in a horse in South Africa. Several recent reports exist of neurological disease associated with lineage 2 WNV in humans and horses in South Africa and Europe; however, there are a lack of sequencing data from recent fatal cases in Southern Africa, where these strains likely originate. A better understanding of the genetic composition of highly neuroinvasive lineage 2 strains may facilitate the identification of putative genetic factors associated with increased virulence.

96 Meseko, CA, Ehizibolo DO, Nwokike EC, Wungak YS. (2016) Serological evidence of equine influenza virus in horse stables in Kaduna, Nigeria. J Equine Sci.;27(3):99-105. Abstract Equine influenza virus (EIV) is a major cause of acute respiratory diseases in horses in most parts of the world that results in severe economic losses. Information on the epidemiology of EIV in tropical Africa is scanty. An enzyme-linked immunosorbent assay (ELISA) was used to detect the presence of influenza A virus nucleoprotein (NP) in 284 horse sera in Kaduna State, Northern Nigeria. The ELISA-positive sera were further examined for hemagglutination inhibition (HI) antibodies to two strains each of H3N8 and H7N3 subtypes of influenza A virus. The results showed that antibodies against influenza A virus nucleoprotein were detected in 60.9% (173 of 284) of horses examined by NP-ELISA. Equine H3 and H7 subtypes were detected in 60% (21 of 35) and 20% (7 of 35) of horse sera respectively across the stables. Adequate quarantine of all imported horses, a national equine influenza surveillance plan and an appropriate EIV control program in Nigeria are recommended to safeguard the large horse population.

97 Metz, Germán Ernesto, et.al. (2016) Intrinsic, extrinsic and endoplasmic reticulum stress-induced apoptosis in RK13 cells infected with equine arteritis virus.- Virus Research 213 (2016) 219–223. Abstract The modulation of the expression of caspases by viruses influences the cell survival of different cell types. Equine arteritis virus (EAV) induces apoptosis of BHK21 and Vero cell lines, but it is not known whether EAV induces apoptosis in RK13 cells, a common cell line routinely used in EAV diagnosis and research. In this study, we determined that caspase-3 expression was triggered after infection of RK13 cells with EAV in a time- and dose-dependent manner. We also detected caspase-8 and caspase-9 activation, indicating the stimulation of both extrinsic and intrinsic apoptosis pathways. Finally, we found caspase-12 activation, an indicator of endoplasmic reticulum stress-induced apoptosis. The variability observed in the apoptotic response in the different cell lines demonstrates that apoptosis depends on the distinctive sensitivity of each cell line used for investigation. 98 Miller, D, et.al. (2016) Polymorphism at expressed DQ and DR loci in five common equine MHC haplotypes. Immunogenetics. 2016 Nov 26. Abstract The polymorphism of major histocompatibilitycomplex (MHC) class II DQ and DR genes in five common equine leukocyte antigen (ELA) haplotypes was determined through sequencing of mRNA transcripts isolated from lymphocytes of eight ELA homozygous horses. Ten expressed MHC class II genes were detected in horses of the ELA-A3 haplotype carried by the donor horses of the equine bacterial artificial chromosome (BAC) library and the reference genome sequence: four DR genes and six DQ genes. The other four ELA haplotypes contained at least eight expressed polymorphic MHC class II loci. Next generation sequencing (NGS) of genomic DNA of these four MHC haplotypes revealed stop codons in the DQA3 gene in the ELA- A2, ELAA5, and ELA-A9 haplotypes. Few NGS reads were obtained for the other MHC class II genes that were not amplified in these horses. The amino acid sequences across haplotypes contained locus-specific residues, and the locus clusters produced by phylogenetic analysis were well supported. The MHC class II alleles within the five tested haplotypes were largely non-overlapping between haplotypes. The complement of equine MHC class II DQ and DR genes appears to be well conserved between haplotypes, in contrast to the recently described variation in class I gene loci between equine MHC haplotypes. The identification of allelic series of equine MHC class II loci will aid comparative studies of mammalian MHC conservation and evolution and may also help to interpret associations between the equine MHC class II region and diseases of the horse.

99 Miño S, Barrandeguy M, Parreño V, Parra GI. (2016) Genetic linkage of capsid protein-encoding RNA segments in group A equine rotaviruses. J Gen Virol. 97(4):912-21. Abstract Rotavirus virions are formed by three concentric protein layers that enclose the 11 dsRNA genome segments and the viral proteins VP1 and VP3. Interactions amongst the capsid proteins (VP2, VP6, VP7 and VP4) have been described to play a major role in viral fitness, whilst restricting the reassortment of the genomic segments during co-infection with different rotavirus strains. In this work we describe and characterize the linkage between VP6 and VP7 proteins based on structural and genomic analyses of group A rotavirus strains circulating in Argentinean horses. Strains with the VP7 genotype G3 showed a strong association with the VP6 genotype I6, whilst strains with G14 were associated with the I2 genotype. Most of the differences on the VP6 and VP7 proteins were observed in interactive regions between the two proteins, suggesting that VP6 : VP7 interactions may drive the co-evolution and co-segregation of their respective gene segments.

100 Mondal, Shankar P., et.al. (2016) Development and characterization of a synthetic infectious cDNA clone of the virulent Bucyrus strain of equine arteritis virus expressing mCherry (red fluorescent protein).0 Archiver of Viology, 161: 821-832 Abstract Strains of equine arteritis virus (EAV) differ in their virulence phenotypes, causing anywhere from subclinical infections to severe disease in horses. Here, we describe the in silico design and de novo synthesis of a fulllength infectious cDNA clone of the horse-adapted virulent Bucyrus strain (VBS) of EAV encoding mCherry along with in vitro characterization of the progeny virions (EAV sVBSmCherry) in terms of host-cell tropism, replicative capacity and stability of the mCherry coding sequences following sequential passage in cell culture. The relative stability of the mCherry sequence during sequential cell culture passage coupled with a comparable host-cell range phenotype (equine endothelial cells, CD3? T cells and CD14? monocytes) to parental EAV VBS suggest that EAV-sVBSmCherry-derived virus could become a valuable research tool for identification of host-cell tropism determinants and for characterization of the viral proteins involved in virus attachment and entry into different subpopulations of peripheral blood mononuclear cells. Furthermore, this study demonstrates that advances in nucleic acid synthesis technology permit synthesis of complex viral genomes with overlapping genes like those of arteriviruses, thereby circumventing the need for complicated molecular cloning techniques. In summary, de novo nucleic acid synthesis technology facilitates innovative viral vector design without the tedium and risks posed by more-conventional laboratory techniques.

101 Mönki, J, Hewetson M, Virtala AM. (2016) Risk Factors for Equine Gastric Glandular Disease: A Case Control Study in a Finnish Referral Hospital Population. J Vet Intern Med.;30(4):1270-5. Abstract Background: Equine gastric glandular disease (EGGD) is a term used to classify erosive and ulcerative diseases of the glandular mucosa of the equine stomach. Epidemiologic studies of risk factors for EGGD have not been reported. Objective: To determine risk factors for EGGD. Animals: Cases (n = 83) had endoscopic evidence of EGGD; controls (n = 34) included healthy horses and horses with equine squamous gastric disease (ESGD) without EGGD. Methods: Retrospective case-control study. The data were analyzed by multivariable logistic regression modeling. Analysis was performed on the full dataset. An additional analysis compared horses with glandular lesions (n = 43) against healthy horses (n = 22). Results: On first analysis, Warmblood breed (OR = 13.9, 95% CI 2.2–90.9, P = .005) and an increasing number of caretakers (OR = 7.3, 95% CI 0.98–55.6, P = .053) were associated with an increased risk of EGGD. On analysis of the subset of data, Warmblood breed (OR = 28.6, 95% CI 2.96–250.0, P = .004) and increasing number of riders (OR = 12.99, 95% CI 0.94–166.7, P = .056) were risk factors. The presence of sand in the colon appeared to have a protective effect against EGGD (OR = 0.195, 95% CI 0.04–1.0, P = .051 for sand versus not having sand). Conclusions and clinical importance: This study suggests that Warmbloods are predisposed to EGGD and multiple handlers/riders might increase the risk of EGGD. Identification of risk factors allows speculation on potential pathophysiological mechanisms of EGGD.

102 Morsy K, et.al. (2016) Description of two equine nematodes, Parascaris equorum Goeze 1782 and Habronema microstoma Schneider 1866 from the domestic horse Equus ferus caballus (Famisly: Equidae) in Egypt. Parasitol Res.;115(11):4299-4306. Abstract Parasitic gastroenteritis (PGE) caused by infection of the gut with parasitic nematodes is one of the most important diseases of livestock animals from both financial and welfare perspectives. Parascaris equorum and Habronema microstoma are of the most endemic nematodes of the world which are currently the major cause of PGE of the domestic horses in Egypt. The present investigation introduced the first morphological description of these nematodes recovered from the domestic horse, Equus ferus caballus (Equidae), in Egypt by light and scanning electron microscopy. Seven P. Equorum (fifth stage) and 18 adults of H. microstoma were recovered from the gastrointestinal tracts of four young domestic horses collected during the year of 2015. Microscopic examination of the isolated fifth stage P. equorum revealed that it possessed a long body with a broad anterior end equipped by large shamrock-like lips with deep transverse groove on medial surface set off from the rest of the body by a deep post-labial constriction giving the body a shouldered appearance. The total body length was 12–15 (14 ± 2) cm for males and 13– 18 (16 ± 2) cm for females. Lips were three in number in the form of one dorsal and two sub-ventral surrounding the central stoma. The isolated adult worms of H. Microstoma were whitish in color narrowed slightly at the anterior end. Single lateral ala in the cephalic region in both sexes was observed. The buccal vestibule was markedly thickened and equipped by two tridentate teeth. The adult worms had two bilobed lateral lips surrounding the mouth with four submedian cephalic papillae and two amphids. The males were 14.5–18.0 (17.2 ± 0.3) mm long and 1.23–1.57 (1.42 ± 0.3) mm wide. The posterior end was spirally coiled and had wide caudal alae. The spicules were unequal. The females were 13.5– 21.0 (16.2 ± 0.3) mm long and 1.55–1.75 (1.69 ± 0.3) mm wide. The anal pore had a thin upper rim and was located 177.0 μm from the posterior end.

103 Nardini R, et.al. (2016) Validation according to OIE criteria of a monoclonal, recombinant p26- based, serologic competitive enzyme-linked immunosorbent assay as screening method in surveillance programs for the detection of Equine infectious anemia virus antibodies. J Vet Diagn Invest.;28:88-97. Abstract The Italian National Reference Center for equine infectious anemia (CRAIE; Rome, Italy) developed and validated a monoclonal, recombinant p26–based competitive enzyme-linked immunosorbent assay (cELISA) for the detection of EIA virus antibodies employing the 2010 criteria of the World Organization for Animal Health (OIE). The following parameters were evaluated: cutoff values, repeatability, reproducibility, concordance, analytical sensitivity (Se), absolute analytical specificity (Sp), and diagnostic Se and Sp. Positive and negative predictive values were also defined in relation to the estimated prevalence. When the cELISA was used as a screening test for 96,468 samples in the Italian EIA surveillance program, 17% more EIA cases were detected than by the agar gel immunodiffusion test, and the apparent diagnostic Sp estimated from these samples was 99.8%, which was more than the diagnostic Sp (80.2%) estimated from validation. The high Se and Sp of the cELISA confirm its fit for purpose as a screening test

104 Nicholls VM, Townsend N. (2016) Dental Disease in Aged Horses and Its Management. Vet Clin North Am Equine Pract.,32(2):215-27. Abstract Dental disorders are common in the equine geriatric population. Age-related changes in normal equine dentition result in dental disorders.Geriatric patients have specific requirements for restraint and sedation. A key point is ensuring oral comfort and maximizing masticatory ability. Dental treatment in geriatric patients often requires concurrent management changes, such a dietary modification and treatment of coexisting problems, such as pituitary pars intermedia dysfunction (PPID).

105 Niedzwiedz A,et.al. (2016) Serum 8-hydroxy-2-deoxyguanosine as a marker of DNA oxidative damage in horses with recurrent airway obstruction. Acta Vet Scand. ;58(1):38. Abstract Background: It has been reported that equine recurrent airway obstruction (RAO) is a state of oxidative stress. Oxidant-antioxidant imbalance is known to increase the conversion of deoxyguanosine to 8-hydroxy-2- deoxyguanosine (8-OHdG) in DNA. 8-OHdG can easily be measured using ELISA tests in serum or urine samples. In this study, we analysed serum 8-OHdG levels in horses with recurrent airway obstruction and in healthy controls. Results: The study material consisted of seven healthy horses and seven horses with symptomatic RAO. All horses were exposed to moldy hay and straw for 48 h to induce clinical exacerbation of RAO. The serum 8-OHdG levels were determined using the ELISA Highly Sensitive 8-OHdG kit. The difference between the levels of 8-OHdG in healthy and RAO-affected horses was significant. The median level of 8-OHdG was 0.044 ng/ml in the healthy controls versus 0.498 ng/ml in RAO horses (P = 0.0021). Conclusions: The results of the study strongly suggest that DNA damage coexists in the course of equine RAO. We therefore propose that future research should aim at the development of new drugs that target pro- inflammatory molecules, since DNA damage appears to be the result of chronic inflammation

106 Oliver J, et.al. (2016) Geography and Timing of Cases of Eastern Equine Encephalitis in New York State from 1992 to 2012. Vector Borne Zoonotic Dis.;16(4):283-9. Abstract Introduction: In New York State (NYS), Eastern equine encephalitis (EEE) was first reported in a human in 1971, in horses in 1970, and in pheasants in 1952. Material and Method: Following work for the interval from 1970 to 1991, we identified cases in vertebrates from 1992 to 2012, through a passive surveillance system involving veterinarians in clinical practice, county health departments, and the Departments of Agriculture and Markets, Environmental Conservation, and Health, of the State of New York. Result: During an 11-year hiatus, from 1992 to 2002, no case in any vertebrate was observed. In a reemergence, from 2003 to 2012, disease occurred in 12 counties, including 7 counties where disease had never been documented. Vertebrate cases included 4 cases in humans and 77 nonhuman occurrences; in 58 horses, Equus ferus caballus L.; 2 deer, Odocoileus virginianus Zimmermann; 6 dogs, Canis familiaris; 10 birds; and 1 flock of pheasants, Phasianus colchicus L. These were the first reported cases in NYS in white-tailed deer, the domestic dog, and in five species of birds: American crow, Corvus brachyrhynchos Brehm; American goldfinch, Carduelis tristis L.; bald eagle, Haliaeetus leucocephalus L.; blue jay, Cyanocitta cristata (L.); and redtailed hawk, Buteo jamaicensis Gmelin. One crow was dually infected with EEE virus and West Nile virus. The northern, southern, and southeastern borders of the state were newly affected. Conclusion: The geographic area, time periods, and vertebrate species with risk of EEE disease expanded from 1992 to 2012.

107 Olofsson, TC, et.al. (2016) Pathogens in Horses with Honeybee Lactic Acid Bacteria. Curr Microbiol.;73(4):463-73. Abstract In the global perspective of antibiotic resistance, it is urgent to find potent topical antibiotics for the use in human and animal infection. Healing of equine wounds, particularly in the limbs, is difficult due to hydrostatic factors and exposure to environmental contaminants, which can lead to heavy bio-burden/biofilm formation and sometimes to infection. Therefore, antibiotics are often prescribed. Recent studies have shown that honeybeespecific lactic acid bacteria (LAB), involved in honey production, and inhibit human wound pathogens. The aim of this pilot study was to investigate the effects on the healing of hard-to-heal equine wounds after treatment with these LAB symbionts viable in a heather honey formulation. For this, we included ten horses with wound duration of[1 year, investigated the wound microbiota, and treated wounds with the novel honeybee LAB formulation. We identified the microbiota using MALDI-TOF mass spectrometry and DNA sequencing. In addition, the antimicrobial properties of the honeybee LAB formulation were tested against all wound isolates in vitro. Our results indicate a diverse wound microbiota including fifty-three bacterial species that showed 90 % colonization by at least one species of Staphylococcus. Treatment with the formulation promoted wound healing in all cases already after the first application and the wounds were either completely healed (n = 3) in less than 20 days or healing was in progress. Furthermore, the honeybee LAB formulation inhibited all pathogens when tested in vitro. Consequently, this new treatment option presents as a powerful candidate for the topical treatment of hard-to-heal wounds in horses

108 Orard M,et.al. (2016) Influence of bronchoalveolar lavage volume on cytological profiles and subsequent diagnosis of inflammatory airway disease in horses. Vet J.; 207: 193-5. Abstract The aim of the study was to determine whether instillation of either 250 mL or 500 mL of saline for broncho- alveolar lavage (BAL) would influence cytological confirmation of 40 inflammatory airway disease (IAD). Thirty client-owned Standardbred racehorses were 41 sampled via endoscopy with 250 mL of saline in one lung and 500 mL in the contralateral 42 lung. The procedure was repeated 72 h later, reversing the volume per lung. The proportions 43 of BAL fluid (BALF) recovered were significantly higher and neutrophil percentages 44 significantly lower with the larger volume. A poor agreement was found between 45 methodologies in terms of final diagnosis, when based on proportions of neutrophils (> 10% 46 from at least one lung). Within the recommended range (250-500 mL), the instilled volume 47 significantly influenced cytological profiles. Establishing specific BALF reference values are 48 warranted. 49

109 Pedersen, Kerri, et.al. (2016) Widespread Detection of Antibodies to Eastern Equine Encephalitis, West Nile, St. Louis Encephalitis, and Turlock Viruses in Various Species of Wild Birds from Across the United States. Am. J. Trop. Med. Hyg., 95(1): 206–211. Abstract Wild birds serve as amplifying hosts for many arboviruses, and are thought to be responsible for introducing these viruses into new areas during migration as well as reintroducing them to places where winter temperatures disrupt mosquito-borne transmission. To learn more about four mosquito-borne arboviruses of concern to human or animal health, we tested sera from 997 wild birds of 54 species and 17 families across 44 states of the United States collected from January 1, 2013, through September 30, 2013. Samples were tested for antibody against eastern equine encephalitis, St. Louis encephalitis, West Nile, and Turlock viruses using plaque reduction neutralization tests with an endpoint of 80% or greater. Of the 333 (33.4%) birds that tested positive for antibody to at least one arbovirus, 29.7% were exposed to two or more arboviruses. Exposure to all four arboviruses was detected in Canada geese, double-crested cormorants, mallards, mute swans, laughing gulls, and American coots. Our results suggest that exposure to arboviruses is widespread in the United States across a diversity of wild bird species.

110 Paillot, R,. .. (2016) The Use of a Recombinant Canarypox-Based Equine Influenza Vaccine during the 2007 Australian Outbreak: A Systematic Review and Summary. Pathogens.;5(2). pii: E42. Abstract: In 2007, Australia experienced the most extensive equine influenza outbreak observed in recent years. Extraordinary measures were rapidly implemented in order to control and prevent the spread of this highly contagious disease. The control strategy involved stringent movement restriction and disease surveillance, seconded by emergency post-outbreak vaccination strategies. Sixteen months after the first case and 12 months following the last reported case, Australia regained its equine influenza-free OIE status. This systematic review reports and summarises information relating to the implementation of emergency vaccination during the 2007 Australian equine influenza outbreak, including the choice of vaccine and implementation strategies

111 Parreira, DR,et.al. (2016) Health and epidemiological approaches of Trypanosoma evansi and equine infectious anemia virus in naturally infected horses at southern Pantanal. Acta Trop.;163:98-102. Abstract Equine infectious anemia virus (EIAV) and Trypanossoma evansi are endemic in Brazilian Pantanal Biome, an important area for livestock production. In this sense, we evaluated the epidemiological single and coinfection effects of T. evansi and EIAV in naturally infected horses in the southern Pantanal wetland by serological tests and hematological assays. Both higher seroprevalence and heath poor condition of the sampled animals were associated with differences in horse management between farms. We found that the negative animals for both infectious agents (NN) represented the major group in F1 (37%), and the smallest group in F2 (19%). Furthermore, we recorded higher EIAV seroprevalence (56%) in F2, compared to F1 (38%). We observed that T. evansi infection was mostly related to young horses, as seen by their higher seroprevalence, ranging from 70.7% in the beginning of the rainy season to 81% in the end of flood period, in comparison with the values of 42% and 68%, respectively, in working animals. on the other hand, working animals showed a higher seroprevalence for EIAV (48%) in both seasons than young horses. We observed that the management of working horses could be a risk factor of EIAV infection. On the other hand, as T. evansi is mantained in the study region by many species of wild mammals, the mechanical transmission through blood-sucking vectors ensures the infection to horses since early. Our results showed that single or co-infection by EIAV and T. evansi caused different degree of anemia in the infected animals. Moreover, the health of horses in Brazilian Pantanal is also influenced by differences in horse management and environmental circumstances.

112 Perglione CO,et.al. (2016) Epidemiological and virological findings during multiple outbreaks of equine influenza in South America in 2012. Influenza Other Respir Viruses.;10:37-46. Abstract Background In 2012, equine influenza (EI) virus was confirmed as the cause of outbreaks of respiratory disease in horses throughout South America. In Uruguay and Argentina, hundreds of vaccinated thoroughbred horses in training and racing facilities were clinically affected. Objective To characterise the EI viruses detected during the outbreak in Uruguay and Argentina. Methods Virus was detected in nasopharyngeal swabs by a panreactive influenza type A real-time RT-PCR. The nucleotide sequence of the HA1 gene was determined and analysed phylogenetically using MEGA 5 software. Amino acid sequences alignments were constructed and virus was antigenically characterised with specific ferret antisera. Paired serum samples were tested by haemagglutination inhibition and single radial haemolysis. Results The diagnosis of EIV was confirmed by real-time RT-PCR, virus isolation and serological testing. The phylogenetic analysis of HA1 gene sequences of 18 EI viruses indicated that all of them belong to clade 1 of the Florida sublineage of the American lineage and are closely related to viruses isolated in the United States in 2012. The HA1 of viruses identified in horses in racing facilities in Maro~nas, Uruguay, and in Palermo, Argentina, displayed 100% amino acid sequence identity and were identical to that of a virus isolated in Dubai in 2012, from vaccinated endurance horses recently imported from Uruguay. Conclusions The surveillance data reported illustrate the international spread of EI viruses and support the recommendations of the OIE expert surveillance panel to include viruses of the Florida sublineage in vaccines.

113 Pfahl K, Chung C, et.al. (2016) Further evaluation and validation of a commercially available competitive ELISA (cELISA) for the detection of antibodies specific to equine arteritis virus (EAV). Vet Rec.;178(4):95. Abstract The purpose of this study was to further evaluate and validate two commercially available equine arteritis virus (EAV) competitive ELISAs (original and enhanced cELISAs) using archived equine sera from experimentally inoculated animals and field sera submitted for laboratory diagnosis. First, the original and subsequently enhanced cELISAs were compared with the virus neutralisation test (VNT) using a panel of archived serum samples from experimentally inoculated animals. Then, the enhanced cELISA was compared with the VNT using a large panel of archived serum samples. The total number of equine sera tested was 3255, which included sera against 25 different EAV strains. The study confirmed that the enhanced cELISA was more sensitive than the original cELISA. Based on testing sera from experimentally inoculated animals and field sera, the enhanced cELISA had an estimated sensitivity (98.9 percent and 99.6 percent, respectively) and specificity (98.3 percent and 98.7 percent, respectively). The currently marketed enhanced VMRD EAV antibody cELISA test kit (VMRD Inc., Pullman, Washington, USA) has high sensitivity and specificity relative to the VNT. Based on the findings of this study, the authors would propose that the enhanced cELISA should be considered as an alternative approved method to the VNT for the detection of antibodies to EAV 114 Ploeg M, Saey V, van Loon G, Delesalle C. (2016) Thoracic aortic rupture in horses. Equine Vet J. 2016 Oct 26. Abstract The aorta can rupture at the aortic root or aortic arch. In most breeds, the aortic root is the likely site and rupture leads to aortocardiac fistula with communication between the aorta and the right atrium, right ventricle and/or the interventricular septum. There is a high prevalence of aortic rupture in young Friesian horses and rupture occurs at the aortic arch with pseudoaneurysm and potentially aortopulmonary fistulation. Echocardiographic and post-mortem techniques must be adapted to identify aortic arch rupture that is not generally identified with standard approaches. Given the narrow genetic base of the Friesian breed and the significant differences found in extracellular matrix composition and metabolism between Friesians and Warmbloods, genetic factors are likely to contribute to the condition in the Friesian breed.

115 Pozor MA, et.al. (2016) Placental abnormalities in equine pregnancies generated by SCNT from one donor horse. Theriogenology.;86(6):1573-82. Abstract Placental changes associated with somatic cell nuclear transfer (SCNT) have been described in several species, but little information is available in this area in the horse. We evaluated the ultrasonographic, gross and histopathological characteristics of placentas from three successful and five unsuccessful equine somatic cell nuclear transfer (SCNT) pregnancies, established using cells from a single donor horse. Starting at approximately 6 months gestation, the pregnancies were monitored periodically using transrectal (TR) and transabdominal (TA) ultrasonography (US) to examine the placentas, fetal fluids and fetuses. Of the five mares that aborted, one mare did so suddenly without any abnormal signs detected by US, and four had enlarged umbilical vessels visible on TA-US before abortion. Placental edema (TR-US) and intravascular thrombi in the umbilical cords were seen (TA-US) in two of these four mares; one mare aborted shortly after acute placental separation was identified on TA-US. In three mares that delivered live foals,TA-US showed engorged allantoic vessels and enlarged umbilical vessels. Two of these mares had placental thickening visible on TR-US, interpreted as a sign of placentitis, that subsided after aggressive medical treatment. Seven of the eight placentas were submitted for gross and histopathological examinations after delivery. All placentas had some degree of edema, abnormally engorged allantoic vessels, and enlarged umbilical vessels. Placentitis, large allantoic vesicles, cystic pouches in the fetal part of the cord, and hemorrhages and thrombi in the umbilical vessels were detected only in placentas from mares that aborted. Equine pregnancies resulting from SCNT may be associated with placental pathologies that can be detected using ultrasonography. However, interpreting their severity is difficult. While placental abnormalities have been observed in SCNT pregnancies in other species, to the best of our knowledge, placentitis has not been previously reported and may be an important complication of equine SCNT pregnancies, leading to pregnancy loss.

116 Pusterla N, et.al. (2016) Prevalence factors associated with equine herpesvirus type 1 infection in equids with upper respiratory tract infection and/or acute onset of neurological signs from 2008 to 2014. Vet Rec.;178(3):70. Abstract The objective of the present case-control study was to determine prevalence factors associated with the detection of equine herpesvirus type 1 (EHV-1) by quantitative PCR (qPCR) in horses presented to veterinarians with clinical signs related to an upper respiratory tract infection and/or acute onset of neurological disease from March 2008 to December 2014. Nasal secretions and whole blood from 4228 equids with acute onset of fever, respiratory signs and/or neurological deficits were tested by qPCR for EHV-1. Categorical analyses were performed to determine the association between observations and EHV-1. A total of 117/4228 (2.7 per cent) equids tested qPCR-positive for EHV-1, with most of the isolates belonging to the non-neuropathogenic genotype (N752). EHV-1 PCR-positive equids were over-represented in racing horses. Depression, anorexia, nasal discharge and coughing were significantly less frequently reported in the EHV-1 qPCR-positive equids compared with the EHV-1 qPCR-negative cases. Neurological deficits were more frequently reported in the EHV-1 qPCR-positive cases. This study provides contemporary information on the frequency of EHV-1 detection by qPCR in blood and nasal secretions from horses with fever, respiratory signs and neurological deficits.

117 Reed SM,et.al. (2016) Equine Protozoal Myeloencephalitis: An Updated Consensus Statement with a Focus on Parasite Biology, Diagnosis, Treatment, and Prevention. J Vet Intern Med.;30:491-502. Abstract Consensus Statements of the American College of Veterinary Internal Medicine (ACVIM) provide the veterinary community with up-to-date information on the pathophysiology, diagnosis, and treatment of clinically important animal diseases. The ACVIM Board of Regents oversees selection of relevant topics, identification of panel members with the expertise to draft the statements, and other aspects of assuring the integrity of the process. The statements are derived from evidence-based medicine whenever possible and the panel offers interpretive comments when such evidence is inadequate or contradictory. A draft is prepared by the panel, followed by solicitation of input by the ACVIM membership which may be incorporated into the statement. It is then submitted to the Journal of Veterinary Internal Medicine, where it is edited before publication. The authors are solely responsible for the content of the statements

118 Ricotti S, Garcia MI, et.al. (2016) Serologically silent, occult equine infectious anemia virus (EIAV) infections in horses. Vet Microbiol.;187:41-9. Abstract Molecular and serological techniques for Equine Infectious Anemia Virus (EIAV) diagnosis were compared using samples from 59 clinically normal horses stabled on five farms in the Santa Fe Province of Argentina. Of these 26 (44.1%) were positive in official AGID tests and/or gp45/gp90-based ELISA. Surprisingly 18 of the 33 seronegative horses were positive in a PCR against viral sequences encoding gp45 (PCR positive/ AGID- negative) with all but one remaining EIAV-antibody negative throughout a two year observation period. The gp45 PCR results are supported by fact that 7/18 of these horses were positive in the Office International des Epizooties (OIE) recommended EIAV gag gene specific PCR plus 2 of this 7 also reacted in a PCR directed predominantly against the 5’ untranslated region of the viral genome. Furthermore sufficient quantities of serum were available from 8 of these horses to 3 verify their seronegative status in sensitive Western Blot tests and demonstrate by ELISA the absence of EIAV-specific antibodies was not attributable to abnormalities in total IgG concentration. Studies involving 7 of the PCR-positive/AGID-negative horses to measure lymphocyte proliferation in the presence of PHA showed no significant differences between this group and control animals. In addition, lymphocytes from 2 of these 7 horses responded to peptides derived from gp90 and gp45. Together these results demonstrate that apparently clinically normal horses with no gross signs of immunodeficiency in terms of total IgG concentration or T helper-cell function can remain seronegative for at least 24 months while harboring EIAV specific nucleic acid sequences.

119 Robinson CS, Wylie CE, Compston PC, Payne RJ. (2016) Alleviation of Epiphora by Canaliculosinostomy into the Caudal Maxillary Sinus in the Horse. Vet Surg.;45(1):115-20. Abstract Case records of all horses presented for chronic epiphora to a single equine hospital that underwent surgical treatment were reviewed. All included horses had a Jones test or dacryocystography to confirm nasolacrimal duct obstruction. All horses were anesthetized and canaliculosinostomy was created from the medial canthus of the eye into the caudal maxillary sinus using a Steinmann pin and Jacob’s chuck. A Foley catheter was placed normograde through the stoma. The inflated bulb held the Foley in place in the sinus, while the proximal end was pulled through the upper eyelid and sutured to the skin on the head. The Foley catheter was maintained in place for 3 weeks and then removed under sedation. Results: Five horses were included. There were no intraoperative difficulties or complications. One horse dislodged the Foley catheter 3 days postoperatively.No other postoperative complications occurred. Followup was available for all horses. One horse was euthanatized for unrelated reasons 10 weeks postoperative at which time epiphora was resolved. The remaining 4 horses had resolution of epiphora at followup (24–46 months postoperative). 120 Rocha, T. (2016), Contagious equine metritis in Portugal: A retrospective report of the first outbreak in the country and recent contagious equine metritis test results. Open Vet J., 6(3): 263-267 Abstract Contagious equine metritis (CEM), a highly contagious bacterial venereal infection of equids, caused by Taylorella equigenitalis, is of major international concern, causing short-term infertility in mares. Portugal has a long tradition of horse breeding and exportation and until recently was considered CEM-free. However, in 2008, T. equigenitalis was isolated at our laboratory from a recently imported stallion and 2 mares from the same stud. Following this first reported outbreak, the Portuguese Veterinary Authority (DGVA) performed mandatory testing on all remaining equines at the stud (n=30), resulting in a further 4 positive animals. All positive animals were treated and subsequently tested negative for T. equigenitalis. Since this outbreak, over 2000 genital swabs from Portuguese horses have been tested at our laboratory, with no further positive animals identified. The available data suggests that this CEM outbreak was an isolated event and we have no further evidence of CEM cases in Portugal, however, an extended and wider epidemiological study would be needed to better evaluate the incidence of the disease in Portuguese horses

121 DeRouen A, Spriet M, Aleman M. (2016) Prevalence of anatomical variation of the sixth cervical vertebra and association with vertebral canal stenosis and articular process Osteoarthritis in the horse Vet Radiol Ultrasound.;57(3):253-8. Abstract The sixth cervical vertebra (C6) has unique morphology due to a ventral extension from the transverse process known as the ventral lamina. Little information was found regarding the prevalence and clinical relevance of morphologic variations. Aims of this observational, retrospective study were to characterize C6 morphologic variations in a large sample of horses. Cervical radiographic studies of 100 horses were retrieved. Data recorded were signalment, clinical history, morphology of the C6 ventral lamina, presence of articular process osteoarthritis, and presence of static vertebral canal stenosis. Morphologic variations were found in C6 vertebrae for 24/100 horses, with symmetric absence of the ventral lamina in nine horses and asymmetric absence in 15. Anomalous C6 vertebrae were more common in Warmbloods, with 19/55 Warmbloods in the population being affected (P = 0.006). No association was found with sex. There was no significant difference in the mean of the intravertebral sagittal ratios between horses with normal or anomalous C6 vertebrae; however there was a significantly greater proportion of horses with anomalous C6 vertebrae that had an intravertebral sagittal ratio of less than 0.5 at C6 (P = 0.047). There was no association between the morphology of C6 and articular process osteoarthritis. Anomalous C6 vertebrae in our population were associated with a higher likelihood of cervical pain (P = 0.013). Authors propose that morphologic variations in the C6 ventral laminae could be linked to other developmental abnormalities such as vertebral canal stenosis, might affect regional biomechanics and should therefore be considered clinically relevant in horses. Future, controlled prospective studies are needed to test this theory.

122 Rütten, S, Schusser GF, Abraham G, Schrödl W. (2016) Release kinetics of tumor necrosis factor-α and interleukin-1 receptor antagonist in the equine whole blood. BMC Vet Res.;12(1):117. Abstract Background: Horses are much predisposed and susceptible to excessive and acute inflammatory responses that cause the recruitment and stimulation of polymorphnuclear granulocytes (PMN) together with peripheral blood mononuclear cells (PBMC) and the release of cytokines. The aim of the study is to develop easy, quick, cheap and reproducible methods for measuring tumor necrosis factor alpha (TNF-α) and interleukin-1 receptor antagonist (IL-1Ra) in the equine whole blood cultures ex-vivo time- and concentration-dependently. Results: Horse whole blood diluted to 10, 20 and 50 % was stimulated with lipopolysaccharide (LPS), PCPwL (a combination of phytohemagglutinin E, concanavalin A and pokeweed mitogen) or equine recombinant TNF- α (erTNF-α). TNF-α and IL-1Ra were analyzed in culture supernatants, which were collected at different time points using specific enzyme-linked immunosorbent assays (ELISA). Both cytokines could be detected optimal in stimulated 20 % whole blood cultures. TNF-α and IL-1Ra releases were time-dependent but the kinetic was different between them. PCPwL-induced TNF-α and IL-1Ra release was enhanced continuously over 24–48 h, respectively. Similarly, LPS-stimulated TNF-α was at maximum at time points between 8–12 h and started to decrease thereafter, whereas IL-1Ra peaked later between 12–24 h and rather continued to accumulate over 48 h. The equine recombinant TNF-α could induce also the IL-1Ra release. Conclusions: Our results demonstrate that similar to PCPwL, LPS stimulated TNF-α and IL-1Ra production time-dependently in whole blood cultures, suggesting the suitability of whole blood cultures to assess the release of a variety of cytokines in health and diseases of horse.

123 Sarkar, Sanjay, et.al. Allelic Variation in CXCL16 Determines CD3+ T Lymphocyte Susceptibility to Equine Arteritis Virus Infection and Establishment of Long- Term Carrier State in the Stallion.- PLoS Genet 12(12): e1006467. Abstract Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory, systemic, and reproductive disease of horses and other equid species. Following natural infection, 10±70% of the infected stallions can become persistently infected and continue to shed EAV in their semen for periods ranging from several months to life. Recently, we reported that some stallions possess a subpopulation(s) of CD3+ T lymphocytes that are susceptible to in vitro EAV infection and that this phenotypic trait is associated with longterm carrier status following exposure to the virus. In contrast, stallions not possessing the CD3+ T lymphocyte susceptible phenotype are at less risk of becoming long-term virus carriers. A genome wide association study (GWAS) using the Illumina Equine SNP50 chip revealed that the ability of EAV to infect CD3+ T lymphocytes and establish long-term carrier status in stallions correlated with a region within equine chromosome 11. Here we identified the gene and mutations responsible for these phenotypes. Specifically, the work implicated three allelic variants of the equine orthologue of CXCL16 (EqCXCL16) that differ by four non-synonymous nucleotide substitutions (XM_00154756; c.715 A!T, c.801 G!C, c.804 T!A/G, c.810 G!A) within exon 1. This resulted in four amino acid changes with EqCXCL16S (XP_001504806.1) having Phe, His, Ile and Lys as compared to EqCXL16R having Tyr, Asp, Phe, and Glu at 40, 49, 50, and 52, respectively. Two alleles (EqCXCL 16Sa, EqCXCL16Sb) encoded identical protein products that correlated strongly with longterm EAV persistence in stallions (P<0.000001) and are required for in vitro CD3+ T lymphocyte susceptibility to EAV infection. The third (EqCXCL16R) was associated with in vitro CD3+ T lymphocyte resistance to EAV infection and a significantly lower probability for establishment of the long-term carrier state (viral persistence) in the male reproductive tract. EqCXCL16Sa and EqCXCL16Sb exert a dominant mode of inheritance. 124 Sarkar S, et.al. (2016) Equine herpesvirus-1 infection disrupts interferon regulatory factor-3 (IRF-3) signaling pathways in equine endothelial cells. Vet Immunol Immunopathol.;173:1-9. Abstract Equine herpesvirus-1 (EHV-1) is a major respiratory viral pathogen of horses, causing upper respiratorytract disease, abortion, neonatal death, and neurological disease that may lead to paralysis and death.EHV-1 replicates initially in the respiratory epithelium and then spreads systemically to endothelial cellslining the small blood vessels in the uterus and spinal cord leading to abortion and EHM in horses. Likeother herpesviruses, EHV-1 employs a variety of mechanisms for immune evasion including suppressionof type-I interferon (IFN) production in equine endothelial cells (EECs). Previously we have shown thatthe neuropathogenic T953 strain of EHV-1 inhibits type-I IFN production in EECs and this is mediatedby a viral late gene product. But the mechanism of inhibition was not known. Here we show that T953strain infection of EECs induced degradation of endogenous IRF-3 protein. This in turn interfered withthe activation of IRF-3 signaling pathways. EHV-1 infection caused the activation of the NF- _B signalingpathways, suggesting that inhibition of type-I IFN production is probably due to interference in IRF-3 andnot NF- _B signal transduction

125 Sarkar, S, Balasuriya UB, Horohov DW, Chambers TM. (2016) The neuropathogenic T953 strain of equine herpesvirus-1 inhibits type-I IFN mediated antiviral activity in equine endothelial cells. Vet Microbiol.;183:110-8. Abstract Equine herpesvirus-1 (EHV-1) infects equine endothelial cells (EECs) lining the small blood vessels in the central nervous system. However, the effect of type I IFN on EHV-1 replication in the EECs is not well studied. Thus, the primary objective of this study was to investigate the effect of type-I IFN on the replication of the neuropathogenic T953 strain of EHV-1 in vitro in EECs. The initial data showed that the EHV-1 was partly resistant to the biological effect of exogenously supplied recombinant equine IFN-a. Subsequent investigation into the mechanism of resistance showed that EHV-1 infection of EECs interfered with the STAT-1 phosphorylation through which type-I IFN exerts its antiviral effect. Immunofluorescence staining showed interference with the translocation of STAT-1 molecules from cytoplasm to nucleus confirming the virus mediated suppression of STAT-1 activation. Downstream of the JAK-STAT signaling, EHV-1 infection inhibited expression of cellular antiviral proteins including IFN-stimulated gene 56 (ISG56) and viperin. Taken together these findings suggest that the neuropathogenic T953 strain of EHV-1 evades the host innate immune response by inhibiting IFN and this may provide some insight into the pathogenesis of EHV-1 infection.

126 Sarkar, S, et.al. (2016) Equine Arteritis Virus Uses Equine CXCL16 as an Entry Receptor. J Virol.; 90(7):3366-84. Abstract Previous studies in our laboratory have identified equine CXCL16 (EqCXCL16) as a candidate molecule and possible cell entry receptor for equine arteritis virus (EAV). In horses, the CXCL16 gene is located on equine chromosome 11 (ECA11) and encodes a glycosylated, type I transmembrane protein with 247 amino acids. Stable transfection of HEK-293T cells with plasmid DNA encoding EqCXCL16 (HEK-EqCXCL16) increased their permissiveness to EAV infection from <3% to almost 100% of the cell population. The increase in permissiveness was blocked either by transfection of HEK-EqCXCL16 cells with siRNAs directed against EqCXCL16 or by pre-treatment with guinea pig polyclonal antiserum against EqCXCL16 protein (Gp α- EqCXCL16 pAb). Furthermore, using a virus overlay protein-binding assay (VOPBA) in combination with Far-Western blotting, gradient purified EAV particles were shown to bind directly to the EqCXCL16 protein in vitro. The binding of biotinylated EAV virulent Bucyrus strain at 4 °C was significantly higher in HEK- EqCXCL16 cells compared to non-transfected HEK cells. Finally, the results demonstrated that EAV preferentially infects subpopulations of horse CD14+ monocytes expressing EqCXCL16 and that infection of these cells is significantly reduced by pretreatment with Gp α-EqCXCL16 pAb. The collective data from this study provides confirmatory evidence that the transmembrane form of EqCXCL16 likely plays a major role in EAV host-cell entry processes possibly acting as a primary receptor molecule for this virus.

127 Simeonova GP, Krastev SZ, Simeonov RS. (2016) Immunological and pathological investigations in equine experimental uveitis. Vet Res Commun.,40(3-4):107-115. Abstract Background The pathogenic mechanism of equine recurrent uveitis (ERU) is still poorly defined andmany variations between experimental animal models and spontaneous disease exist. Objectives The aim of our study was to investigate if Th17 cell-mediated response plays role in the pathogenesis of the used experimental model in horses and to reveal its pathological findings. Methods Experimental uveitis was induced in 6 healthy horses. The concentrations of retinal autoantigen CRALBP and IL-17 were measured using ELISA in aqueous humor and vitreous body of the 12 inflamed eyes as well as in 12 control non-inflamed eyes taken from 6 horses in slaughter house. After centrifugation of the two eye media, smears were prepared and cytological investigation was performed. Tissue specimens were taken from all eye globes and were submitted to histopathological investigation. Results CRALBP and IL-17 concentrations were significantly elevated in eye media of horses with experimental uveitis in comparison with controls. Cytological and histopathological findings corresponded to the changes characteristic of chronic immune-mediated inflammation with mononuclear cell infiltration of uvea, choroid, retina, and eye media as well as severe retinal destruction. Conclusions Our study demonstrated the involvement of the retinal autoantigen CRALBP as well as IL-17 in the pathogenesis of experimental uveitis in horses. These findings suggests that this experimental uveitis in horses may serve as a suitable animal model for investigation of IL-17- mediated immune response during spontaneous autoimmune uveitis in horses as well as in humans 128 Slivinska, K,et.al. (2016) Molecular surveillance of Theileria equi and Anaplasma phagocytophilum infections in horses from Ukraine, Poland and Slovakia. Vet Parasitol.;215:35-7. Abstract A survey was undertaken to assess the prevalence of Theileria equi and Anaplasma phagocytophilum in some regions of Ukraine, Poland and Slovakia. Using a specific PCR assays, blood samples from 215 horses were tested. The prevalence of T. equi and A. phagocytophilum infection was 13.95% and 1.4%, respectively. BLAST analysis showed the isolates closest to the T. equi 18S rRNA and A. phagocytophilum msp4 gene sequences in GenBank with a similarity of ≥99%. No significant association was found between the T. Equi PCR positivity and the age or sex of the horses. There was a significant association between the origin of horses and T. equi - PCR positivity. No significant association was found between the A. phagocytophilum - PCR positivity and the age, sex or origin.

129 Tsegay, K, Potts AD, Aklilu N, Lötter C, Gummow B. (2016) Circulating serovars of Leptospira in cart horses of central and southern Ethiopia and associated risk factors. Prev Vet Med.;125:106-15. Abstract Little work has been done on diseases of horses in Ethiopia or tropical regions of the world. Yet, Ethiopia has the largest horse population in Africa and their horses play a pivotal role in their economy as traction animals. A serological and questionnaire survey was therefore conducted to determine the circulating serovars of Leptospira and their association with potential risk factors in the cart horse population of Central and Southern Ethiopia. A total of 184 out of 418 cart horses from 13 districts had antibody titres of 1:100 or greater to at least one of 16 serovars of Leptospira species in Central and Southern Ethiopian horses. A significantly higher seropositivity (62.1%) was noted in horses from the highland agroecology followed by midland (44.4%) and lowland (39.8%). Serovar Bratislava (34.5%) was the predominant serovar followed by serovars Djasiman (9.8%), Topaz (5.98%) and Pomona (5.3%). Age and location proved to be associated with seropositive horses with older horses being more commonly affected and the districts of Ziway (Batu) (Apparent Prevalence (AP)=65.5%), Shashemene (AP=48.3%) and Sebeta (AP=41.4%) having the highest prevalence. Multivariable logistic regression found risk factors significantly associated with Leptospira seropositive horses were drinking river water 2(OR=2.8) and horses 7-12 years old (OR=5) and risk factors specifically associated with serovar Bratislava seropositive horses were drinking river water (OR= 2.5), horses ≥13 years (OR=3.5) and the presence of dogs in adjacent neighbouring properties (OR = 0.3). Dogs had a protective effect against seropositivity to serovars Bratislava and Djasiman, which may be due to their ability to control rodents. The high seroprevalence confirm that leptospirosis is endemic among horses of Central and Southern Ethiopia. The predominance of serovar Bratislava supports the idea that serovar Bratislava may be adapted to and maintained by the horse population of Central and Southern Ethiopia. This study emphasizes the need for further countrywide serological surveys and isolation of circulating leptospires in animals and humans in order to understand the role of horses in the epidemiology of this disease.

130 Uddin, MJ,et.al. (2016) Kinetics of the West Nile virus induced transcripts of selected cytokines and Toll-like receptors in equine peripheral blood mononuclear cells. Vet Res.;47(1):61. Abstract West Nile virus (WNV) is one of the most common causes of epidemic viral encephalitis in horses worldwide. Peripheral blood mononuclear cells (PBMCs) are amongst the first to encounter the virus following a mosquito bite. This study aimed to elucidate the transcription kinetics of cytokine, Toll-like receptor (TLRs) and TLRs- associated genes following WNV challenge of equine PBMCs. PBMCs were challenged with an Australian strain of WNV (WNVNSW2011) and transcriptomes were quantified at 2, 6, 12 and 24 h post-infection (pi) using qRT-PCR. Type I and II interferons (IFNα, β and γ) mRNA transcription increased following WNV exposure, as did the transcripts for IL1α, IL1β, IL6, IL8, and IL22, but with slightly varying kinetics. TLR1, 3, 5, 7-9 transcripts were also upregulated in equine PBMCsin response to WNV challenge, as were those for MyD88, NF-κB, TRAF3, STAT1 and 2, IRF3 and 7, ISG15, as well as SOCS1 and 3 compared to the control cells. Expression of selected genes in the draining lymph node, spleen and brain (medulla oblongata) of experimentally infected horses was also assessed and transcription of most of these genes was also upregulated here. Although qRT-PCR detected higher viral RNA at 24 h pi compared to 6 h pi, the virus did not replicate productively in equine PBMCs. The up-regulation of gene-transcription for selected cytokines, IFNs, TLRs and TLRs-associated molecules suggests their involvement in virus recognition and control of WNV infection in the horse.

131 Vaz PK, Horsington J,et.al.(2016) Evidence of widespread natural recombination among field isolates of equine herpesvirus 4 but not among field isolates of equine herpesvirus 1. J Gen Virol.;97:747-55. Abstract Recombination in alphaherpesviruses allows evolution to occur in viruses that have an otherwise stable DNA genome with a low rate of nucleotide substitution. High-throughput sequencing of complete viral genomes has recently allowed natural (field) recombination to be studied in a number of different alphaherpesviruses, however, such studies have not been applied to equine herpesvirus 1 (EHV-1) or equine herpesvirus 4 (EHV- 4). These two equine alphaherpesviruses are genetically similar, but differ in their pathogenesis and epidemiology. Both cause economically significant disease in horse populations worldwide. This study used highthroughput sequencing to determine the full genome sequences of EHV-1 and EHV-4 isolates (11 and 14 isolates, respectively) from Australian or New Zealand horses. These sequences were then analysed and examined for evidence of recombination. Evidence of widespread recombination was detected in the genomes of the EHV-4 isolates. Only one potential recombination event was detected in the genomes of the EHV-1 isolates, even when the genomes from an additional 11 international EHV-1 isolates were analysed. The results from this study reveal another fundamental difference between the biology of EHV-1 and EHV-4. The results may also be used to help inform the future safe use of attenuated equine herpesvirus vaccines.

132 van Weeren, PR, Back W. (2016) Musculoskeletal Disease in Aged Horses and Its Management. Vet Clin North Am Equine Pract. Aug;32(2):229-47. Abstract Musculoskeletal disease is the most prevalent health and welfare issue in aged horses with osteoarthritis (OA) and chronic laminitis being the most common single disorders. The prevalence of OA is greater than 50% in horses older than 15 years and up to 80% to 90% in horses over 30. Management of OA in the elderly horse is multifocal and focuses, apart from pain management, also on optimizing the exercise regimen and improving living conditions. Laminitis in the geriatric horse is related to pituitary pars intermedia dysfunction (PPID) in many cases. Laminitis in geriatric horses is managed as in the general horse population, with additional benefit from pergolide administration in PPID cases.

133 Welsh, CE, Duz M, Parkin TD, Marshall JF. (2016) Prevalence, survival analysis and multimorbidity of chronic diseases in the general veterinarian-attended horse population of the UK. Pre Med;131: 137-45. Abstract The average age of the global human population is increasing, leading to increased interest in the effectsof chronic disease and multimorbidity on health resources and patient welfare. It has been posited thatthe average age of the general veterinarian-attended horse population of the UK is also increasing, andtherefore it could be assumed that chronic diseases and multimorbidity would pose an increasing risk herealso. However, evidence for this trend in ageing is very limited, and the current prevalence of many chronicdiseases, and of multimorbidity, is unknown. Using text mining of first-opinion electronic medical recordsfrom seven veterinary practices around the UK, Kaplan-Meier and Cox proportional hazard modelling,we were able to estimate the apparent prevalence among veterinarian-attended horses of nine chronicdiseases, and to assess their relative effects on median life expectancy following diagnosis. With thesemethods we found evidence of increasing population age. Multimorbidity affected 1.2% of the studypopulation, and had a significant effect upon survival times, with co-occurrence of two diseases, andthree or more diseases, leading to 6.6 and 21.3 times the hazard ratio compared to no chronic disease,respectively. Laminitis was involved in 74% of cases of multimorbidity. The population of horses attendedby UK veterinarians appears to be aging, and chronic diseases and their co-occurrence are commonfeatures, and as such warrant further investigation.

134 Witkowski, L, et.al. (2016) Molecular epidemiology of Rhodococcus equi in slaughtered swine, cattle and horses in Poland. BMC Microbiol.;16:98. Abstract Background: Rhodococcus equi is an emerging zoonotic presumably foodborne pathogen. Since the data on the worldwide prevalence of R. equi in meat animals are scarce, the present study aimed to investigate the molecular epidemiology of R. equi in swine, cattle and horse carcasses intended for human consumption in Poland. Results: Totally 1028 lymph node samples were examined. R. equi was isolated from 26.6 % (105/395) swine and 1. 3 % (3/234) bovine healthy submaxillary lymph nodes. In horses, R. equi was isolated only from 0.5 % (1/198) samples of middle tracheo-branchiales lymph node while no lymphocentrum retropharyngeum sample was positive (0/198). The purulent lesions were observed only in 0.8 % swine submaxillary lymph nodes samples (3/398) and in two of them R. equi was detected. All bovine and most of swine isolates (98.1 %) were vapB-positive. 87.9 % of swine isolates carried 95-kb type 5 plasmid, 3.7 % type 1 and plasmid types: 4, 7, 10, 11, 21, 31 were carried by a single isolate (0.9 %). All bovine isolates carried VAPB type 26. Single horse isolate was vapA-positive and carried plasmid VAPA 85-kb type I. Conclusions: The prevalence of vapB-positive R. equi in investigated healthy swine intended for human consumption was very high. Not only swine, but also even apparently healthy cattle or horse carcasses should be considered as a potential source of R. equi for humans, especially in countries where undercooked or raw beef or horsemeat is traditionally consumed.

135 Woo, PC, Lau SK,et.al. (2016) Equine rhinitis B viruses in horse fecal samples from the Middle East. Virol J.;13:94. Abstract Background: Among all known picornaviruses, only two species, equine rhinitis A virus and equine rhinitis B virus (ERBV) are known to infect horses, causing respiratory infections. No reports have described the detection of ERBV in fecal samples of horses and no complete genome sequences of ERBV3 are available. Methods: We performed a molecular epidemiology study to detect ERBVs in horses from Dubai and Hong Kong. Complete genome sequencing of the ERBVs as well as viral loads and genome, phylogenetic and evolutionary analysis were performed on the positive samples. Results: ERBV was detected in four (13.8 %) of the 29 fecal samples in horses from Dubai, with viral loads 8.28 × 103 to 5.83 × 104 copies per ml, but none of the 47 fecal samples in horses from Hong Kong by RT- PCR. Complete genome sequencing and phylogenetic analysis showed that three of the four strains were ERBV3 and one was ERBV2. The major difference between the genomes of ERBV3 and those of ERBV1 and ERBV2 lied in the amino acid sequences of their VP1 proteins. The Ka/Ks ratios of all the coding regions in the ERBV3 genomes were all <0.1, suggesting that ERBV3 were stably evolving in horses. Using the uncorrelated lognormal distributed relaxed clock model on VP1 gene, the date of the most recent common ancestor (MRCA) of ERBV3 was estimated to be 1785 (HPDs, 1176 to 1937) and the MRCA dates of ERBV1 and ERBV2 were estimated to be 1848 (HPDs, 1466 to 1949) respectively. Conclusions: Both acid stable (ERBV3) and acid labile (ERBV2) ERBVs could be found in fecal samples of horses. Detection of ERBVs in fecal samples would have implications for their transmission and potential role in gastrointestinal diseases as well as fecal sampling as an alternative method of identifying infected horses. 136 Yamanaka T, et.al. (2016) Evaluation of twenty-two rapid antigen detection tests in the diagnosis of Equine Influenza caused by viruses of H3N8 subtype. Influenza Other Respir Viruses.; 10(2):127-33 Abstract Background Equine influenza (EI) is a highly contagious disease caused by viruses of the H3N8 subtype. The rapid diagnosis of EI is essential to reduce the disease spread. Many rapid antigen detection (RAD) tests for diagnosing human influenza are available, but their ability to diagnose EI has not been systematically evaluated. Objectives The aim of this study was to compare the performance of 22 RAD tests in the diagnosis of EI. Methods The 22 RAD tests were performed on fivefold serial dilutions of EI virus to determine their detection limits. The four most sensitive RAD tests (ImmunoAce Flu, BD Flu examan, Quick chaser Flu A, B and ESPLINE Influenza A&B-N) were further evaluated using nasopharyngeal samples collected from experimentally infected and naturally infected horses. The results were compared to those obtained using molecular tests. Results The detection limits of the 22 RAD tests varied hugely. Even the four RAD tests showing the best sensitivity were 125-fold less sensitive than the molecular techniques. The duration of virus detection in the experimentally infected horses was shorter using the RAD tests than using the molecular techniques. The RAD tests detected between 27% and 73% of real-time RT-PCR-positive samples from naturally infected horses. Conclusions The study demonstrated the importance of choosing the right RAD tests as only three of 22 were fit for diagnosing EI. It was also indicated that even RAD tests with the highest sensitivity serve only as an adjunct to molecular tests because of the potential for false-negative results.

137 Jing Zhao, et.al. Dual infections of equine herpesvirus 1 and equine arteritis virus inequine respiratory mucosa explants.- Virus Research 220 (2016) 104–111. Abstract Equine herpesvirus 1 (EHV-1) and equine arteritis virus (EAV) induce respiratory problems and abortionin horses and are considered as two serious threats to equine industry. Both EHV-1 and EAV misusepatrolling leukocytes in the upper respiratory tract to breach the basement membrane (BM) and tomigrate to blood vessels. So far, the behavior and impact of a double infection in the respiratory mucosaof a horse are unknown. In the present study, the outcome of double infections with EHV-1 and thelow virulent EAV strain 08P187 (superinfection with an interval of 12 h or co-infection) were comparedwith single infections in fully susceptible RK-13 cells and equine upper respiratory mucosa explants.When RK-13 cells were inoculated with either EHV-1 or EAV 12 h prior to the subsequent EAV or EHV-1inoculation, the latter EAV or EHV-1 infection was clearly suppressed at 24 hpi or 36 hpi, respectively,without EHV-1 and EAV co-infecting the same RK-13 cells. After simultaneous infection with EHV-1and EAV, higher numbers of EAV infected cells but similar numbers of EHV-1 infected cells were foundcompared to the single infections, with a low number of EHV-1 and EAV co-infected RK-13 cells at 48 hpiand 72 hpi. In the upper respiratory mucosa exposed to EAV 12 h prior to EHV-1, the number and size ofthe EHV-1-induced plaques were similar to those of the EHV-1 single infected mucosa explants. In nasaland nasopharyngeal mucosae, EAV and EHV-1 pre-infections slightly reduced the number of EHV-1 andEAV infected leukocytes compared to the single infections and co- infection. In double EAV and EHV-1infected explants, no co-infected leukocytes were detected. From these results, it can be concluded thatEAV and EHV-1 are only slightly influencing each other’s infection and that they do not infect the samemucosal leukocytes. 138 Yao S, Liu J,et.al. (2016) Structural Illumination of Equine MHC Class I Molecules Highlights Unconventional Epitope Presentation Manner That Is Evolved in Equine Leukocyte Antigen Alleles. J Immunol.;196(4):1943-54. Abstract MHC class I (MHC I)–restricted virus-specific CTLs are implicated as critical components in the control of this naturally occurring lentivirus and in the protective immune response to the successfully applied attenuated equine infectious anemia virus vaccine in the horse. Nevertheless, the structural basis for how the equine MHC I presents epitope peptides remains unknown. In this study, we investigated the binding of several equine infectious anemia virus–derived epitope peptides by the ability to refold recombinant molecules and by thermal stability, and then by determining the x-ray structure of five peptide–MHC I complexes: equine MHC class I allele (Eqca)-N*00602/Env-RW12, Eqca-N*00602/Gag-GW12, Eqca-N*00602/Rev-QW11, Eqca-N*00602/ Gag-CF9, and Eqca-N*00601/Gag-GW12. Although Eqca-N*00601 and Eqca-N*00602 differ by a single amino acid, Eqca-N*00601 exhibited a drastically different peptide presentation when binding a similar CTL epitope, Gag-GW12; the result makes the previously reported function clear to be non–cross-recognition between these two alleles. The structures plus Eqca-N*00602 complexed with a 9-mer peptide are particularly noteworthy in that we illuminated differences in apparent flexibility in the center of the epitope peptides for the complexes with Gag-GW12 as compared with Env-RW12, and a strict selection of epitope peptides with normal length. The featured preferences and unconventional presentations of long peptides by equine MHC I molecules provide structural bases to explain the exceptional anti-lentivirus immunity in the horse. We think that the beneficial reference points could serve as an initial platform for other human or animal lentiviruses 139 Ziegler, A, Marti E, Summerfield A, Baumann A. (2016) Identification and characterization of equine blood plasmacytoid dendritic cells. Dev Comp Immunol;65: 352-7. Abstract Dendritic cells (DC) are antigen-presenting cells that can be classified into three major cell subsets: conventional DC1 (cDC1), cDC2 and plasmacytoid DCs (pDC), none of which have been identified in horses. Therefore, the objective of this study was to identify and characterize DC subsets in equine peripheral blood, emphasizing on pDC. Surface marker analysis allowed distinction of putative DC subsets, according to their differential expression of CADM-1 and MHC class II. Equine pDC were found to be Flt3þ CD4low CD13_ CD14_ CD172a_ CADM-1_ MHCIIlow. The weak expression of CD4 on equine pDC contrasts with findings in several other mammals. Furthermore, pDC purified by fluorescence-activated cell sorting were found to be the only cell subset able to produce large amounts of IFN-a upon TLR9-agonist stimulation. The pDC identity was confirmed by demonstrating high-levels of PLAC8, RUNX2 and TCF4 expression, showing pDC-restricted expression in other mammals.

140 Zucca, E, et.al. (2016) Evaluation of amniotic mesenchymal cell derivatives on cytokine production in equine alveolar macrophages: an in vitro approach to lung inflammation. Stem Cell Res Ther; 7(1):137. Abstract Background: Data obtained in both animal models and clinical trials suggest that cell-based therapies represent a potential therapeutic strategy for lung repair and remodeling. Recently, new therapeutic approaches based on the use of stem cell derivatives (e.g., conditioned medium (CM) and microvesicles (MVs)) to regenerate tissues and improve their functions were proposed. The aim of this study was to investigate the immunomodulatory effects of equine amniotic mesenchymal cell derivatives on lipopolysaccharide (LPS)-induced cytokine production in equine alveolar macrophages, which may be beneficial in lung inflammatory disorders such as recurrent airway obstruction (RAO) in horses. RAO shares many features with human asthma, including an increased number of cells expressing mRNA for interleukin (IL)-4 and IL-5 and a decreased expression of IFN- γ in bronchoalveolar lavage fluid (BALF) of affected horses. Methods: The release of TNF-α, IL-6, and TGF- β1 at different time points (1, 24, 48, and 72 h) was measured in equine alveolar macrophages stimulated or not with LPS (10 and 100 ng/mL) in the presence or absence of 10 % CM or 50 × 106 MVs/mL. Cytokines were measured using commercially available ELISA kits. For multiple comparisons, analysis of variance was used with Tukey post-hoc test. Differences were considered significant at p ≤ 0.05. Results: Significant modulatory effects of CM on LPS-induced TNF-α release at 24 h, and of both CM and MVs on TNF-α release at 48 h were observed. A trend toward a modulatory effect of both CM and MVs on the release of TGF-β and possibly IL-6 was visible over time.Conclusions: Results support the potential use of CM and MVs in lung regenerative medicine, especially in situations in which TGF-β may be detrimental, such as respiratory allergy. Further studies should evaluate the potential clinical applications of CM and MVs in equine lung diseases, such as RAO and other inflammatory disorders.

141 Abdelgawad A, et.al. (2015) Comprehensive Serology Based on a Peptide ELISA to Assess the Prevalence of Closely Related Equine Herpesviruses in Zoo and Wild Animals. PLoS One.;10(9):e0138370. Abstract Equine herpesvirus type 1 (EHV-1) causes respiratory disorders and abortion in equids while EHV-1 regularly causes equine herpesvirus myeloencephalopathy (EHM), a strokelike syndrome following endothelial cell infection in horses. Both EHV-1 and EHV-9 infections of non-definitive hosts often result in neuronal infection and high case fatality rates. Hence, EHV-1 and EHV-9 are somewhat unusual herpesviruses and lack strict host specificity, and the true extent of their host ranges have remained unclear. In order to determine the seroprevalence of EHV-1 and EHV-9, a sensitive and specific peptide-based ELISA was developed and applied to 428 sera from captive and wild animals representing 30 species in 12 families and five orders. Members of the Equidae, Rhinocerotidae and Bovidae were serologically positive for EHV-1 and EHV-9. The prevalence of EHV-1 in the sampled wild zebra populations was significantly higher than in zoos suggesting captivity may reduce exposure to EHV-1. Furthermore, the seroprevalence for EHV-1 was significantly higher than for EHV- 9 in zebras. In contrast, EHV-9 antibody prevalence was high in captive and wild African rhinoceros species suggesting that they may serve as a reservoir or natural host for EHV-9. Thus, EHV-1 and EHV-9 have a broad host range favoring African herbivores and may have acquired novel natural hosts in ecosystems where wild equids are common and are in close contact with other perissodactyls.

142 Allen, LJ, Schwartz EJ. (2015) Free-virus and cell-to-cell transmission in models of equine infectious anemia virus infection. Math Biosci.;270(Pt B):237-48. Abstract Equineinfectiousanemiavirus(EIAV)isalentivirusintheretrovirusfamilythatinfectshorsesandponies.Twostrains,re ferredtoasthesensitivestrainandtheresistantstrain,havebeenisolatedfromanexperimental lyinfectedpony. The sensitive strain isvulnerable to neutralization by antibodies where as there sistant strainis neutralization insensitive.The sensitive strain mutates to the resistant strain. EIAVmayinfec the althy target cellsviafree virus oral ternatively,directlyfroman infected target cell throughcell-to- celltransfer.Theproportionoftransmissionfromfree-virus or from cell-to cell transmission is unknown. A system of ordinary differential equations(ODEs) is formulated for thevirus-cell dynamics of EIAV. In addition, aMarkovchain model and abranching process approximation near the infection-freee quilibrium(IFE) are formulated. The basic reproduction number R0 is defined as the maximum of two reproduction numbers, R0sandR0r, one for the sensitive strain andone for theres istant strain.The IFE is shown tobe global lyasymptoticallystable forthe ODE model in a special casewhen the basic reproduction number is less than one. Inaddition,twoendemic equilibria exist, acoexistence equilibrium and aresistant strain equilibrium. It is shown that if R0>1,the infection persists with atleastone of the twostrains. However,for small infectious doses,the sensitive strain and the resistant strain maynot persistin the Markov chain model. Parameter values applicable to EIAVareused to illustrate the dynamics of the ODEand the Markov chain models.The examples highlight the importance of the proportion of cell-to-cellversus free-virus transmission thateither leads to infection clearance or to infection persistence with eitherco existence of both strains or todominance by the resistant strain.

143 Argo CM, Dugdale AH, McGowan CM. (2015) Considerations for the use of restricted, soaked grass hay diets to promote weight loss in the management of equine metabolic syndrome and obesity. Vet J.;206(2):170-7. Abstract The addition of hay soaking to current nutritional advice for weight loss management for equine obesity lacks clinical evidence. Twelve overweight/obese horses and ponies were used to test the hypothesis that feeding soaked hay at 1.25% of body mass (BM) daily as dry matter (DM) before soaking, would elicit weight losses within the target 0.5-1.0% of BM weekly. Six animals were used to evaluate the impact of nutrient leaching on the digestibility and daily intakes of dietary energy and nutrients. Soaked hay DM was corrected in accordance with the ‘insoluble’ ADF content of fresh and soaked hays. The ADF-based method was validated using a test- soaking protocol. Animals fed soaked hay for 6 weeks lost 0.98 ± 0.10% of BM weekly. The most weight loss sensitive animal lost ~2% of BM weekly. Soaking hay did not alter DM gross energy concentrations, incurred losses of water soluble carbohydrates (WSC) and ash and increased acid detergent fibre (ADF) concentrations. Digestibilities of GE, DM, ash and WSC were unaltered but soaking increased uncorrected values for crude protein (+12%) and ADF (+13.5%) digestibility. Corrected DM provision was only 1% of BM daily, providing 64% of maintenance DE requirements, a 23.5% increase in the intended magnitude of energy restriction. Hay soaking leached nutrients, reduced DM and DE provision and was associated with accelerated weight losses over those expected had fresh-hay been fed to the same level. The ADF-based method will allow the predictive evaluation of individual hays to direct feeding management and prevent inadvertently severe DM and energy restriction.

144 Aharonson-Raz K, et.al (2015)Seroprevalence of Leishmania infantum and Toxoplasma gondii in the Horse Population in Israel. Vector Borne Zoonotic Dis.;15(12):726-31. Abstract A cross-sectional investigation was done on the seroprevalence of Leishmania infantum and Toxoplasma gondii infection among apparently healthy horses in Israel. This survey included 383 horses distributed in 22 farms throughout Israel during the years 2011–2013. Serum samples were tested for the presence of immunoglobulin G (IgG) antibodies using the direct agglutination test (DAT) specific to Leishmania and by the modified agglutination test (MAT) for the presence of IgG antibodies to T. gondii. Low seroprevalences were detected for both L. infantum and T. gondii in the horse population in Israel; of the 338 horses tested, 6 (1.4%) were found to be seropositive for L. infantum and 11 (2.5%) for T. gondii, with no significant association between seroprevalence and demographic/environmental factors. An ongoing geographical expansion of L. infantum, previously reported in humans and dogs in Israel, was also supported by our results in horses. Here we present evidence of exposure of horses to L. infantum and T. gondii in Israel. Continuous seroprevalence surveillance in horses, such as the one performed in this study, might further elucidate the eco-epidemiology of these two important zoonotic parasites in this country.

145 Aréchiga-Ceballos N, Aguilar-Setién A. (2015) Alphaviral equine encephalomyelitis (Eastern, Western and Venezuelan). Rev Sci Tech.;34(2):491-501. Abstract Alphaviral equine encephalomyelitis is a mosquito-borne infection that causes severe neurological disease and fatalities in horses and humans in the Americas. Consequently, the equine alphaviruses (Eastern, Western and Venezuelan) are of considerable concern worldwide and are notifiable to the World Organisation for Animal Health. In addition, these diseases are considered a potent potential biological weapon, emphasising the need to develop an effective vaccine. Alphaviral equine encephalomyelitis is caused by Eastern equine encephalomyelitis virus (EEEV), Western equine encephalomyelitis virus (WEEV) or Venezuelan equine encephalomyelitis virus (VEEV), which are related members of the Alphavirus genus in the Togaviridae family. Although related, the three viruses are genetically and antigenically distinct. The disease is characterised by fever, anorexia, depression and clinical signs of encephalomyelitis, and may be fatal in up to 90% of cases, for both humans and horses, particularly in the case of EEE. Surviving horses develop lifelong immunity but may have permanent neuropathology. The aim of this paper is to analyse the scientific information available on the evolution of EEE, WEE and VEE, and any potential vaccines

146 Back H, et.al. (2015) Viral load of equine herpesviruses 2 and 5 in nasal swabs of actively racing Standardbred trotters: Temporal relationship of shedding to clinical findings and poor performance. Vet Microbiol.;179(3-4):142-8. Abstract The equine gamma herpesviruses 2 and 5 (EHV-2 and -5) have frequently been observed in the equine population and until recently presumed low to nonpathogenic. However, recent reports linking presence of equine gamma herpesviruses with clinical signs of mild to severe lung disease, suggest that the role of these viruses in respiratory disease and poor performance syndrome is still unclear. Moreover, baseline data regarding the temporal pattern of shedding of EHV-2 and EHV-5 within stables and within individual actively racing horses have been lacking. In a prospective longitudinal study, we followed elite racing Standardbred trotters at monthly intervals for 13 months, to investigate whether the amount of EHV-2 and EHV-5 shedded in nasal secretions varied over time within and between individual horses. Sixty-six elite horses were investigated by analyzing nasal swabs and serum samples, a health check and evaluation of athletic performance monthly during the study period. Nasal swabs were analyzed with two newly developed qPCR assays for EHV-2 and EHV-5, respectively. Of 663 samples, 197 (30%) were positive for EHV-2 and 492 (74%) positive for EHV-5. Furthermore, 176 (27%) of the samples were positive for both EHV-2 and EHV-5 simultaneously. There was considerable variation in the amount and frequency of shedding of EHV-2 and EHV-5 within and between individual horses. Viral load varied seasonally, but neither EHV-2 nor EHV-5 viral peaks were associated with clinical respiratory disease and/or poor performance in racing Standardbred trotters.

147 Badenhorst M, et.al. (2015) Detection of equine herpesvirus-4 and physiological stress patterns in young Thoroughbreds consigned to a South African auction sale. BMC Vet Res.;11:126. Abstract Background: The prevalence of equine herpesvirus types-1 and -4 (EHV-1 and -4) in South African Thoroughbreds at auction sales is currently undefined. Commingling of young Thoroughbreds from various populations together with physiological stress related to their transport and confinement at a sales complex, may be associated with shedding and transmission of EHV-1 and -4. This prospective cohort study sampled 90 young Thoroughbreds consigned from eight farms, originating from three provinces representative of the South African Thoroughbred breeding demographic to a sales complex. Nasal swabs for quantitative real-time polymerase chain reaction (qPCR) assay to detect EHV-1 and -4 nucleic acid and blood samples for enzyme- linked immunosorbent assay for EHV-1 and -4 antibodies were collected from all horses on arrival and departure. Additional nasal swabs for qPCR were obtained serially from those displaying pyrexia and, or nasal discharge. Daily faecal samples were used for determination of faecal glucocorticoid metabolite (FGM) concentrations as a measurement of physiological stress and these values were modelled to determine the factors best explaining FGM variability. Results: EHV-4 nucleic acid was detected in 14.4 % and EHV-1 from none of the animals in the study population. Most (93.3 %) and very few (1.1 %) of this population showed antibodies indicating prior exposure to EHV-4 and EHV-1 respectively. Pyrexia and nasal discharge were poor predictors for detecting EHV-4 nucleic acid. The horses’ FGM concentrations increased following arrival before decreasing for most of the remaining study period including the auction process. Model averaging showed that variation in FGM concentrations was best explained by days post-arrival and transport duration. Conclusions: In this study population, sales consignment was associated with limited detection of EHV-4 nucleic acid in nasal secretions, with most showing prior exposure to EHV-4 and very few to EHV-1. The physiological stress response shown by most reflected the combination of stressors associated with transport and arrival and these are key areas for future investigation into management practices to enhance health and welfare of young Thoroughbreds during sales consignment.

148 Bartova E,et.al. (2015) Seroprevalence of antibodies of Neospora spp. and Toxoplasma gondii in horses from southern Italy. Folia Parasitol (Praha).;62. pii: 2015.043. Abstract The consumption of horse meat has been epidemiologically linked to clinical toxoplasmosis in humans and neosporosis that may cause clinical illness in horses. Here we determined seroprevalence of antibodies against Toxoplasma gondii Nicolle et Manceaux, 1908 and species of Neospora Dubey, Carpenter, Speer, Topper et Uggla, 1988 in horses from Italy. Blood samples were collected from 643 apparently healthy horses from 60 farms of 51 municipalities in southern Italy. The presence of antibodies against T. gondii and Neospora spp. were detected by indirect fluorescence antibody test (IFAT); a titre ≥ 50 was considered positive. The same sera were also tested for antibodies against Neospora spp. by a competitive-inhibition enzyme-linked immunosorbent assay (cELISA); samples with ≥ 30% inhibition were considered positive. Antibodies against T. gondii and Neospora spp. were detected in 19 (3.0%) and 15 (2.3%) horses by IFAT, respectively, without statistical difference between gender, age and breeds (p-value ≥ 0.05). Antibodies against species of Neospora were detected in 70 (10.9%) horses by cELISA with statistical difference in gender (6.0–18.5%, p-value ≥ 0.05) and breeds (0–19.4%, p-value ≥ 0.05). Although T. gondii infection rates were low, the risk of human infection should not be dismissed, particularly in Italy where consumption of raw or undercooked horse meat has a long tradition.

149 Beck, C, et.al. (2015) A High-Performance Multiplex Immunoassay for Serodiagnosis of Flavivirus-Associated Neurological Diseases in Horses. Biomed Res Int.;2015:678084. Abstract WestNile virus (WNV), Japanese encephalitis virus (JEV), and tick-borne encephalitis virus (TBEV) are flaviviruses responsible for severe neuroinvasive infections in humans and horses.The confirmation of flavivirus infections ismostly based on rapid serological tests such as enzyme-linked immunosorbent assays (ELISAs). These tests suffer from poor specificity, mainly due to antigenic cross-reactivity among flavivirus members. Robust diagnosis therefore needs to be validated through virus neutralisation tests (VNTs) which are time-consuming and require BSL3 facilities.The flavivirus envelope (E) glycoprotein ectodomain is composed of three domains (D) named DI, DII, and DIII, with EDIII containing virus-specific epitopes. In order to improve the serological differentiation of flavivirus infections, the recombinant soluble ectodomain of WNV E (WNV.sE) and EDIIIs (rEDIIIs) of WNV, JEV, and TBEVwere synthesised using the Drosophila S2 expression system. Purified antigenswere covalently bonded to fluorescent beads. The microspheres coupled to WNV.sE or rEDIIIs were assayed with about 300 equine immune sera from natural and experimental flavivirus infections and 172 nonimmune equine sera as negative controls. rEDIII-coupled microspheres captured specific antibodies against WNV, TBEV, or JEV in positive horse sera. This innovative multiplex immunoassay is a powerful alternative to ELISAs and VNTs for veterinary diagnosis of flavivirus-related diseases.

150 Behrens, Nicole E., Laurel J. Gershwin (2015) Immune modulation of T regulatory cells and IgE responses in horsesvaccinated with West Nile virus vaccine combined with a CpG ODN Vaccine. ;33(43): 5764-71 Abstract Hypersensitivity reactions, such as hives or fatal anaphylactic shock, in response to vaccination constitutea health hazard for horses that develop allergies to vaccine components. In such horses vaccination withviral vaccines stimulates an IgE response to non-target antigens. Viral vaccines share contaminating non-target proteins, such as bovine serum albumin (BSA); these antigens can stimulate IgE production witheach exposure. We hypothesized that the addition of a CpG oligodeoxynucleotide (ODN) administeredin conjunction with a West Nile virus vaccine would decrease the IgE response; through up-regulationof T regulatory cells and T helper 1 cells thus decreasing the potential to induce a type 1 hypersensitivityresponse. Thirty adult horses were injected with either CpG ODN or control GpC ODN with a killed WNVvaccine. T regulatory cell numbers and BSA specific IgE concentrations were determined pre and postvaccination. Multicolor flow cytometry was used to evaluate expression of CD4, CD25, and intracellularFoxp3 on PBMCs. Serum concentrations of BSA specific IgE were determined by ELISA. Cell culture super-natants from BSA re-stimulated lymphocytes were evaluated for concentrations of IL-2, IL-4, IL-10, andIFN- _. The inclusion of the CpG ODN significantly increased the differentiation of T regulatory cells inresponse to antigen in vitro and in vivo. A significant inverse correlation was found between T regulatorycell numbers and serum BSA specific IgE concentrations. These results suggest that we can provide a saferalternate vaccination strategy, particularly for horses that have demonstrated a pro-allergic phenotype 151 Bhagwan J, et.al. (2015) Molecular evidence of Theileria equi infection in Hyalomma anatolicum ticks infested on sero-positive Indian horses. Acta Parasitol.;60(2):322-9. Abstract A sizeable Indian equine population is considered to be pre-immune carrier of Theileria equi infection. In this study we confirmed the presence of T. equi specific DNA in Hyalomma anatolicum ticks which were infested on sero-positive horses. Fifty two Indigenous horses were randomly selected from endemic areas and their blood and tick samples were collected. Tick salivary glands and blood samples were processed for separation of DNA and serum, respectively. Serum samples were analyzed by EMA-2ELISA and nine horses were found positive for T. equi specific antibodies. Species-specific primers were designed from EMA-2 gene of T. equi, so as to amplify 398 bp fragment in PCR. The gene fragment was amplified in PCR on the DNA samples (from blood) from these nine sero-positive horses. Corresponding six tick’s DNA samples collected from these nine seropositive animals were observed positive in PCR. Further, qPCR assay demonstrated presence of T. equi DNA in infected tick’s salivary glands, which was also confirmed by microscopic examination of infected acinar. This study concluded that Hyalomma anatolicum ticks infested on T. equi seropositive horses have sporozoite developmental stage in their salivary glands, which is an evidence for transmitting potential of these tick among Indian horse population.

152 Bonelli F, et.al. (2015) Plasma Procalcitonin Concentration in Healthy Horses and Horses Affected by Systemic Inflammatory Response Syndrome. J Vet Intern Med.;29(6):1689-91. Abstract Background: The diseases most frequent associated with SIRS in adult horses are those involving the gastrointestinal tract. An early diagnosis should be the goal in the management of horses with SIRS. Objective: The objective of this study was to evaluate the plasma procalcitonin (PCT) concentration in healthy and SIRS horses to assess differences between the two groups. Animals: Seventy-eight horses (30 healthy and 48 SIRS). Methods: Prospective in vivo multicentric study. Horses were classified as SIRS if at least 2 of the following criteria were met: abnormal leukocyte count or distribution, hyperthermia or hypothermia, tachycardia, tachypnea. Healthy horses showed no clinical or laboratory signs of SIRS. Plasma PCT concentrations were measured with a commercial ELISA assay for equine species. Results were expressed as mean_standard deviation. T-test for unpaired data was performed between healthy and SIRS group. SIRS group was divided in 4 subgroups and t-test was performed between healthy versus each subgroup. Results: PCT concentrations in healthy and SIRS horses were 18.28 _ 20.32 and 197.0 _ 117.0 pg/mL, respectively. T-test showed statistical differences between healthy versus SIRS group and between healthy versus all subgroups. Conclusions and Clinical Importance: Results showed an increase in PCT concentration in SIRS horses as previously reported in humans and dogs. PCT could be used as a single assay in equine practice for detection of SIRS.

153 Boukharta M, et.al. (2015) Multiple alignment comparison of the non-structural genes of three strains of equine influenza viruses (H3N8) isolated in Morocco. BMC Res Notes.;8:471. Abstract Background: Three equine influenza viruses, A/equine/Nador/1/1997(H3N8), A/equine/Essaouira/2/2004 (H3N8), and A/equine/Essaouira/3/2004(H3N8), were isolated from different Equidae during local respiratory disease outbreaks in Morocco in 1997 and 2004. Their non-structural (NS) genes were amplified and sequenced. Results: The results show high homology of NS nucleotide sequences of A/equine/Nador/1/1997 with European strains (i.e., A/equine/newmarket/2/93 and A/equine/Grobois/1/1998) and clustered into the European lineage. However, NS gene of A/equine/Essaouira/2/2004(H3N8) and A/equine/Essaouira/3/2004 (H3N8) strains indicated high homology with equine influenza strains that had circulated before 1990 (A/equine/Fontainbleu/1/ 1979 (H3N8), which belonged to a pre-divergent phase Amino acid sequence comparison of the NS1 protein with reference strain A/ equine/Miami/1963(H3N8) shows that the A/equine/Nador/1/1997(H3N8) strain has 12 substitutions at the residues D/24/N, R/44/K, S/48/I, R/67/Q, A/86/V, E/139/K, A/112/T, E/186/K, L/185/F, A/223/E, S/213/T and S/228/P. In both A/equine/Essaouira /2/2004(H3N8) and A/equine/Essaouira/3/2004 (H3N8) strains, the NS1 sequences present one common mutation at the residue: S/228/P. Conclusion: It seems that all of these substitutions are not produced at the key residues of the RNA-binding domain (RBD) and the effector domain (ED). Consequently, we can suppose that they will not affect the potency of inhibition of cellular defences, and the virulence of the Moroccan equine strains will be maintained

154 Boysen C,et.al.( 2015) Bayesian Geostatistical Analysis and Ecoclimatic Determinants of Corynebacterium pseudotuberculosis Infection among Horses. PLoS One.;10(10):e0140666. Abstract Kansas witnessed an unprecedented outbreak in Corynebacterium pseudotuberculosis infection among horses, a disease commonly referred to as pigeon fever during fall 2012. Bayesian geostatistical models were developed to identify key environmental and climatic risk factors associated with C. pseudotuberculosis infection in horses. Positive infection status among horses (cases) was determined by positive test results for characteristic abscess formation, positive bacterial culture on purulent material obtained from a lanced abscess (n = 82), or positive serologic evidence of exposure to organism (_1:512)(n = 11). Horses negative for these tests (n = 172)(controls) were considered free of infection. Information pertaining to horse demographics and stabled location were obtained through review of medical records and/or contact with horse owners via telephone. Covariate information for environmental and climatic determinants were obtained from USDA (soil attributes), USGS (land use/land cover), and NASA MODIS and NASA Prediction of Worldwide Renewable Resources (climate). Candidate covariates were screened using univariate regression models followed by Bayesian geostatistical models with and without covariates. The best performing model indicated a protective effect for higher soil moisture content (OR = 0.53, 95% CrI = 0.25, 0.71), and detrimental effects for higher land surface temperature (_35°C) (OR = 2.81, 95% CrI = 2.21, 3.85) and habitat fragmentation (OR = 1.31, 95% CrI = 1.27, 2.22) for C. pseudotuberculosis infection status in horses, while age, gender and breed had no effect. Preventative and ecoclimatic significance of these findings are discussed

155 Brault, Aaronic C., Ying Farng, William K. Reisen (2015) Multiplex qRT-PCR for the Detection of Western Equine Encephalomyelitis, St. Louis Encephalitis, and West Nile Viral RNA in Mosquito Pools (Diptera: Culicidae). J Med Entomol. 2015;52(3): 491-9 Abstract Following the introduction of West Nile virus into California during the summer of 2003, public health and vector control programs expanded surveillance efforts and were in need of diagnostics capable of rapid, sensitive, and specific detection of arbovirus infections of mosquitoes to inform decision support for intervention. Development of a multiplex TaqMan or real-time semiquantitative reverse transcription polymerase chain reaction (RT-PCR) assay in which three virus specific primer–probe sets were used in the same reaction is described herein for the detection of western equine encephalomyelitis, St. Louis encephalitis and West Nile viral RNA. Laboratory validation and field data from 10 transmission seasons are reported. The comparative sensitivity and specificity of this multiplex assay to singleplex RT-PCR as well as an antigen detection (rapid analyte measurement platform) and standard plaque assays indicate this assay to be rapid and useful in providing mosquito infection data to estimate outbreak risk. 156 Breuil, M. - F., et.al. (2015) Contagious equine metritis cases reported in France since 2006. Vet Rec. ;177(13):340. Abstract

157 Cavalcante AL,et.al. (2015) Complete Genome Sequence of Corynebacterium pseudotuberculosis Strain E19, Isolated from a Horse in Chile. Genome Announc.;3(6). pii: e01385-15. Abstract Corynebacterium pseudotuberculosis is related to several diseases infecting horses and small ruminants, causing economic losses to agribusiness. Here, we present the genome sequence of C. pseudotuberculosis strain E19. The genome includes one circular chromosome 2,367,956 bp (52.1% G_C content), with 2,112 genes predicted, 12 rRNAs, and 48 tRNAs.

158 Chaintoutis SC,et.al. (2015) Evaluation of Cross-Protection of a Lineage 1 West Nile Virus Inactivated Vaccine against Natural Infections from a Virulent Lineage 2 Strain in Horses, under Field Conditions. Clin Vaccine Immunol.;22(9): 1040-9. Abstract Although experimental data regarding cross-protection of horse West Nile virus (WNV) vaccines against lineage 2 infections exist, the cross-protective efficacy of these vaccines under field conditions has not been demonstrated. This study was conducted to evaluate the capability of an inactivated lineage 1 vaccine (Equip WNV) to protect against natural infections from the Nea Santa-Greece-2010 lineage 2 strain. In total, 185 WNV-seronegative horses in Thessaloniki, Greece, were selected during 2 consecutive years (2011 and 2012); 140 were immunized, and 45 were used as controls. Horses were examined for signs compatible with WNV infection. Neutralizing antibody titers against the Greek strain and the PaAn001/France lineage 1 strain were determined in immunized horses. WNV circulation was detected during both years in the study area. It was estimated that 37% and 27% of the horses were infected during 2011 and 2012, respectively. Three control animals developed clinical signs, and the WNV diagnosis was confirmed. Signs related to WNV infection were not observed in the vaccinated animals. The nonvaccinated animals had a 7.58%_1.82% higher chance of exhibiting signs than immunized animals (P<0.05). Neutralizing antibodies raised against both strains in all immunized horses were detectable 1 month after the initial vaccination course. The cross-protective capacity of the lowest titer (1:40) was evident in 19 animals which were subsequently infected and did not exhibit signs. Neutralizing antibodies were detectable until the annual booster, when strong anamnestic responses were observed (geometrical mean titer ratio [GMTR] for lineage 1 of 30.2; GMTR for lineage 2 of 27.5). The results indicate that Equip WNV is capable of inducing cross-protection against natural infections from a virulent lineage 2 WNV strain in horses.

159 Chen, Jie, Xinggang Guo, and Lianwei Li (2015) Identification of a Novel Conserved B Cell Epitope in the N Protein of Equine Arteritis Virus (Bucyrus Strain).- Viral Immunology, 28: 391-396. Abstract The nucleocapsid (N) protein is the most conserved structural protein in equine arteritis virus (EAV). This study aimed to identify the minimal conserved B cell epitope on the EAV N protein. The purified N protein was used to immunize mice for preparing monoclonal antibody (mAb). The reactivity of mAb was evaluated by Western blot and immunofluorescence assay. Moreover, 11 overlapping peptides (named MBP-N1 to MBPN11) were designed to localize the linear antigenic epitope within the N protein. The peptides were identified by indirect enzyme-linked immunosorbent assay (ELISA) and Western blot. The minimal conserved B cell epitope on the EAV N protein was identified. The homology analysis was also performed. An EAV N- reactive mAb was selected and designated as 1C11. Indirect ELISA results showed that overlapping domain between MBPN10 and MBP-N11 was recognized by the mAb 1C11. Furthermore, the indirect ELISA and Western blot showed that 101QRKVAP106 was the minimal linear epitope of the EAV N protein. The homology analysis showed that the identified epitope was conserved among all EAV strains analyzed in this work, with the exception of the ARVAC. One EAV N-specific mAb (1C11) was developed, and a minimal linear peptide epitope (101QRKVAP106) within the N protein was identified.

160 Chung, CJ, et.al. (2015) Enhanced sensitivity of an antibody competitive blocking enzyme-linked immunosorbent assay using Equine arteritis virus purified by anion-exchange membrane chromatography. J Vet Diagn Invest.;27(6):728-38. Abstract In an effort to improve a competitive blocking enzyme-linked immunosorbent assay (cELISA) for antibody detection to Equine arteritis virus (EAV), antigen purified by anion-exchange membrane chromatography capsule (AEC) was evaluated. Virus purification by the AEC method was rapid and easily scalable. A comparison was made between virus purified by the AEC method with that obtained by differential centrifugation based on the following: 1) the relative purity and quality of EAV glycoprotein 5 (GP5) containing the epitope defined by monoclonal antibody 17B7, and 2) the relative sensitivity of a commercial antibody cELISA with the only change being the 2 purified antigens. On evaluation by Western blot using GP5-specific monoclonal antibody 17B7, the AEC-purified EAV contained 86% GP5 monomer whereas the differentially centrifuged EAV contained <29% of the monomer. Improvement of analytical sensitivity without sacrifice of analytical specificity was clearly evident when cELISAs prepared with EAV antigen by each purification method were evaluated using 7 sensitivity and specificity check sets. Furthermore, the AEC- purified EAV–based cELISA had 30–40% higher agreement with the virus neutralization (VN) test than the cELISA prepared with differentially centrifuged EAV based on testing 40 borderline EAV-seropositive samples as defined by the VN test. In addition, the AEC-purified cELISA had highly significant (P = 0.001) robustness indicated by intra-laboratory repeatability and interlaboratory reproducibility when evaluated with the sensitivity check sets. Thus, use of AEC-purified EAV in the cELISA should lead to closer harmonization of the cELISA with the World Organization for Animal Health–prescribed VN test.

161 Cohen, Noah D.,et.al. (2015)Gallium Maltolate as an Alternative to Macrolides for Treatment of Presumed Rhodococcus equi Pneumonia in Foals. J Vet Intern Med;29:932–939. Abstract Background: Macrolide-resistant isolates of Rhodococcus equi are emerging, prompting the search for clinically effective alternative antimicrobials. Hypothesis: The proportion of foals with ultrasonographic evidence of pneumonia presumed to be caused by R. equi that had a successful outcome when administered gallium maltolate (GaM) PO would not be more than 10% inferior (ie, lower) than that of foals receiving standard treatment. Animals: Fifty-four foals with subclinical pulmonary abscesses among 509 foals at 6 breeding farms in Kentucky. Methods: Controlled, randomized, prospective noninferiority study. Foals with ultrasonographic lesions >1 cm in diameter (n = 54) were randomly allocated to receive per os either clarithromycin combined with rifampin (CLR+R) or GaM, and followed up for 28 days by daily physical inspections and weekly (n = 1 farm) or biweekly (n = 4 farms) thoracic ultrasound examinations by individuals unaware of treatment-group assignments. Treatment success was defined as resolution of ultrasonographically identified pulmonary abscesses within 28 days of initiating treatment. Noninferiority was defined as a 90% confidence interval for the observed difference in CLR+R minus GaM that was ≤10%. Results: The proportion of GaM-treated foals that resolved (70%; 14/20) was similar to that of foals treated with CLR+R (74%; 25/34), but we failed to demonstrate noninferiority for GaM relative to CLR+R; however, GaM was noninferior to CLR+R treatment when results from a noncompliant farm were excluded. Conclusions and Clinical Importance: Gallium maltolate is not inferior to macrolides for treating foals with subclinical pneumonia. Use of GaM might reduce pressure for macrolide-resistance in R. equi.

162 Dominguez M, Münstermann S, Murray G, Timoney P. (2015) High-health, high-performance' horses: risk mitigation strategies for OIE-listed diseases. Rev Sci Tech.;34(3):837-48. Abstract To address impediments to international competition horse movements and for more countries/regions to be able to benefit from the expansion of the sport horse industry while safeguarding the equine health status of the receiving country, the competing horses, and the equine health status of their home country on their return, the World Organisation for Animal Health (OIE) together with the Fédération Equestre Internationale (FEI) and the International Federation of Horseracing Authorities (IFHA), has developed the “High Health High Performance horse – (HHP)” concept. The concept to establish a high health status subpopulation of horses applies solely to competition horses for temporary entry and not to those used for breeding, or for permanent residency. It is based on the principles of compartmentalisation as defined and described in the Terrestrial Animal Health Code Chapters 4.3 and 4.4. The goal of the OIE in defining such a subpopulation is to provide a rational and scientifically acceptable basis for national animal health authorities to harmonize their entry requirements with respect to the temporary importation of this class of horses. Facilitation of international horse movements is indeed predicated on reducing the number of infectious diseases that horses need to be screened for in transiting from one performance event to another. Such a goal is only achievable, however, if it can be accomplished with minimal risk of dissemination of disease at the event and even more importantly, of introducing an infectious agent into a naïve resident horse population. To qualify as a high health status subpopulation, horses should undergo a specified qualification period. The high health subpopulation is established by the application, at all times, of stringent health management practices and biosecurity procedures to create and maintain a functional separation between horses within the defined subpopulation and all other equids. 163 Du, C, Ma J, et.al. (2015) Mice transgenic for equine cyclin T1 and ELR1 are susceptible to equine infectious anemia virus infection. Retrovirology.;12:36. Abstract Background: As a member of the tumor necrosis factor receptor (TNFR) protein superfamily, equine lentivirus receptor 1 (ELR1) has been shown to be expressed in various equine cells that are permissive for equine infectious anemia virus (EIAV) replication. The EIAV Tat protein (eTat) activates transcription initiated at the viral long terminal repeat (LTR) promoter through a unique mechanism that requires the recruitment of the equine cyclin T1 (eCT1) cofactor into the viral TAR RNA target element. In vitro studies have demonstrated that mouse fibroblast cell lines (e.g., NIH 3T3 cells) that express the EIAV receptor ELR1 and eCT1 support the productive replication of EIAV. Therefore, we constructed transgenic eCT1- and ELR1-expressing mice to examine whether they support in vivo EIAV replication. Findings: For the first time, we constructed mice transgenic for ELR1 and eCT1. Real-time reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis confirmed that ELR1 and eCT1 were expressed in the transgenic mouse tissues, particularly in the intestines, spleen and lymph nodes. Consistent with the results of EIAV infection in NIH 3T3 cells expressing ELR1 and eCT1, mouse embryonic fibroblasts (MEFs) from the transgenic mice could support EIAV replication. More importantly, this virus could infect and replicate in mouse blood monocyte-derived macrophages (mMDMs). Macrophages are the principle target cell of EIAV in its natural hosts. Furthermore, after the transgenic mice were inoculated with EIAV, the virus could be detected not only in the plasma of the circulating blood but also in multiple organs, among which, the spleen and lymph nodes were the predominant sites of EIAV replication. Finally, we found that consistent with high viral replication levels, the relevant pathological changes occurred in the spleen and lymph nodes. Conclusions: Our results show that mice transgenic for ELR1 and eCT1 are susceptible to EIAV infection and replication. Further, EIAV infection can cause lesions on the spleen and lymph nodes, similar to those frequently observed in horses, the natural hosts. Therefore, ELR1 and eCT1 are essential in vivo for EIAV invasion and replication.

164 Duffee LR, Stefanovski D, Boston RC, Boyle AG. (2015) Predictor variables for and complications associated with Streptococcus equi subsp equi infection in horses. J Am Vet Med Assoc.; 247(10):1161-8. Abstract Strangles is an acute infection of the upper portion of the respiratory tract and regional lymph nodes of horses caused by Streptococcus equi subsp equi. The disease is generally characterized by pyrexia, purulent nasal discharge, and abscessed lymph nodes. The infection is contagious, and once strangles has been diagnosed in a horse, intensive biosecurity measures must be implemented to prevent rapid spread of the disease to other horses. Although complications associated with S equi such as purpura hemorrhagica, bastard strangles (metastatic abscesses or culture of S equi from abscesses located in internal organs not associated with the upper portion of the respiratory tract), guttural pouch empyema, and streptococcal myositis have been described, the prevalence of those complications is rarely reported.1,2 During a strangles outbreak on a Standardbred breeding farm, 4 of 205 (2%) horses developed purpura hemorrhagica,3 and investigators estimate that approximately 20% of S equi–infected horses develop bastard strangles.4

165 Feng KH, et.al. (2015) Equine and Canine Influenza H3N8 Viruses Show Minimal Biological Differences Despite Phylogenetic Divergence. J Virol.;89(13):6860-73. Abstract The A/H3N8 canine influenza virus (CIV) emerged from A/H3N8 equine influenza virus (EIV) around the year 2000 through the transfer of a single virus from horses to dogs. We defined and compared the biological properties of EIV and CIV by examining their genetic variation, infection, and growth in different cell cultures, receptor specificity, hemagglutinin (HA) cleavage, and infection and growth in horse and dog tracheal explant cultures. Comparison of sequences of viruses from horses and dogs revealed mutations that may be linked to host adaptation and tropism. We prepared infectious clones of representative EIV and CIV strains that were similar to the consensus sequences of viruses from each host. The rescued viruses, including HA and neuraminidase (NA) double reassortants, exhibited similar degrees of long-term growth in MDCK cells. Different host cells showed various levels of susceptibility to infection, but no differences in infectivity were seen when comparing viruses. All viruses preferred _2-3- over _2-6-linked sialic acids for infections, and glycan microarray analysis showed that EIV and CIV HA-Fc fusion proteins bound only to _2-3-linked sialic acids. Cleavage assays showed that EIV and CIV HA proteins required trypsin for efficient cleavage, and no differences in cleavage efficiency were seen. Inoculation of the viruses into tracheal explants revealed similar levels of infection and replication by each virus in dog trachea, although EIV was more infectious in horse trachea than CIV.

166 Figueiredo AS,et.al. (2015) Identification of two phylogenetic lineages of equine hepacivirus and high prevalence in Brazil. Vet J.;206(3):414-6. Abstract Non-primate hepacivirus (NPHV), as described in horses, is the virus most genetically related to hepatitis C virus (HCV). Although detected worldwide, limited data on genomic variability and distribution of NPHV are available in Latin America. The aim of this study was to investigate the genetic diversity and prevalence of equine NPHV in Brazil. Thirteen percent of 202 equines from three Brazilian states were positive for NPHV genome by reverse transcriptase PCR. Nucleotide sequences of the partial NS5B genome presented the greatest diversity described to date (25.6%), which is comparable to the upper limit of diversity for HCV subtype classification for the same region. Phylogenetic analysis revealed that Brazilian NPHV sequences along with isolates worldwide form two strongly supported clades (pp = 1.0) suggesting the existence of two distinct lineages.

167 Fischer B, Clark-Price S. (2015) Anesthesia of the Equine Neonate in Health and Disease. Vet Clin North Am Equine Pract.;31(3):567-85. Abstract Neonatal foals are different physiologically from adults, resulting in altered pharmacokinetics and pharmacodynamics of anesthetic drugs. Performing anesthesia in the neonatal foal requires attentive monitoring of anesthetic depth, circulation, oxygenation, and ventilation because rapid changes needing intervention are common. Pain pathways are mature at birth, necessitating appropriate administration of analgesics for invasive procedures. The sick neonate frequently has electrolyte, acid–base, and other biochemical derangements that can complicate anesthetic management. Specific research targeting anesthesia in the neonatal foal is lacking, and extrapolation of adult equine information should be done with caution.

168 Fonseca de Araújo Valença SR,et.al. (2015) Risk factors of occurrence of Toxoplasma gondii among horses in the state of Alagoas, Brazil. Acta Parasitol.;60(4):707-11. Abstract The aim of the present study was to investigate the occurrence of Toxoplasma gondii among horses and its associated risk factors in Alagoas, Brazil. In total, 440 samples from 36 properties in 23 districts of the state of Alagoas were studied, covering the Leste, Agreste and Sertão mesoregions. Risk factors were evaluated through the application of an investigative questionnaire that focused on the productive, reproductive and sanitary management of herds. T. gondii infection were assayed using the immunofluorescence assay (IFA) with a cutoff point of 64; 14.4% (95% CI: 11.0%–17.8%) of – horses were seropositive. A significant association was determined between anti-T. gondii antibody presence and the consumption and storage of hay (OR = 2.08 / 95% CI: 1.20–3.62). This is the first report of T. gondii infection among horses in the state of Alagoas, Brazil

169 van Galen G, et.al. (2015) A retrospective study on equine herpesvirus type-1 associated myeloencephalopathy in France (2008-2011). Vet Microbiol.;179(3-4): 304-9. Abstract Diagnosis of equine herpesvirus-1 associated myeloencephalopathy (EHM) can be troublesome, but early recognition and knowledge of risk factors are essential for prevention and control. The objectives for this study are to (1) describe EHM in France, (2) improve clinical recognition, (3) identify risk factors. Through epidemiosurveillance of acute neurological cases (all considered to be potentially infectious cases) in France (2008–2011), 26 EHM cases were identified and 29 EHM negative control cases. EHM cases were described and compared to controls with univariate, multivariate and classification and regression tree analysis. EHM cases had a 46% fatality rate and were frequently isolated cases. Most showed ataxia, paresis and a cauda equina syndrome, yet presence of other neurological signs was variable. Statistical analysis identified the following variables to be significantly associated to EHM compared to controls: introduction of a new horse to the herd, cauda equina syndrome, larger herd size, saddle horses and month of occurrence. The presence of many isolated cases, and less typical and variable clinical presentations emphasize the difficulty in diagnosing EHM. Nevertheless, history and clinical examination of acute neurological cases can be valuable in recognizing EHM early as well in order to select those cases that need further laboratory testing and infection control measures. Moreover, with a different study format and geographic location, risk factors were found to be similar to previous studies, therefore strengthening their significance to the spread of EHM.

170 Galuppi, R, et.al. (2015) Epidemiological survey on Cryptosporidium in an Equine Perinatology Unit. Vet Parasitol.;210(1-2): 10-8. Abstract The present study aims to evaluate the prevalence, pattern of spread and risk factors forthe transmission of cryptosporidiosis in foals and mares hospitalized in a University EquinePerinatology Unit, where a new subtype family of Cryptosporidium horse genotype wasdescribed by Caffara et al. (2013). Mares (36) and foals (37) hospitalized during the 2012foaling season were included. Multiple sampling from each animal was performed (a total of305 stool samples were collected). One hundred and eleven environmental samples (gauzeswabs) were also collected before and after the breeding season. Fourteen foals were foundpositive for Cryptosporidium spp. by PCR in at least one sample; a total of 35 foal stool speci-mens were confirmed for the presence of the protozoa. Instead none of the stool specimensfrom mares were found positive. PCR-RFLP analysis shows Cryptosporidium parvum in 5stool samples and Cryptosporidium horse genotype in 21. In 9 specimens, from 4 differentfoals, the profile was suggestive for a mixed infection. The subtyping at gp60 locus showed2 strains as members of the subtype family IId and six of the subfamily IIa of C. parvum.Twenty isolates were identified as Cryptosporidium horse genotype subtype VIaA15G4. Fivegauze swabs collected from the walls of the boxes where the animals were hosted out of111 environmental samples examined were PCR positive for Cryptosporidium spp. Cryp-tosporidium parvum was detected in one sample collected before the foaling season, whileCryptosporidium horse genotype profile was observed in 4 wall samples collected at the endof the 2012 foaling season. The prevalence observed in foals (37.8%) was higher than thatreported in other studies. These features and the diffusion of the same genotype point outas the EPU, where critically ill foals are hospitalized, can support the spread of cryptospo-ridiosis. Therefore, the manual tasks and the activities carried out in these facilities are ofgreat importance, as they might favor the diffusion of the infection.

171 Giles C, Vanniasinkam T, Barton M, Mahony TJ. (2015) Characterisation of the Equine adenovirus 2 genome. Vet Microbiol.;179(3-4): 184-9. Abstract Equine adenovirus 2 (EAdV-2) is one of two serotypes of adenoviruses known to infect equines. Initial studies did not associate EAdV-2 infections with any specific clinical syndromes, although more recent evidence suggests that EAdV-2 may be associated with clinical and subclinical gastrointestinal infections of foals and adults respectively. In contrast, Equine adenovirus 1 is well recognised as a pathogen associated with upper respiratory tract infections of horses. In this study the complete genome sequence of EAdV-2 is reported. As expected, genes common to the adenoviruses were identified. Phylogenetic reconstructions using selected EAdV-2 genes confirmed the classification of this virus within the Mastadenovirus genus, and supported the hypothesis that EAdV-2 and EAdV-1 have evolved from separate lineages within the adenoviruses. One spliced open reading frame was identified that encoded for a polypeptide with high similarity to the pIX and E1b_55K adenovirus homologues and was designated pIX_E1b_55K. In addition to this fused version of E1b_55K, a separate E1b_55K encoding gene was also identified. These polypeptides do not appear to have evolved from a gene duplication event as the fused and unfused E1b_55K were most similar to E1b_55K homologues from the Atadenovirus and Mastadenovirus genera respectively. The results of this study suggest that EAdV-2 has an unusual evolutionary history that warrants further investigation.

172 Grewar, JD, Thompson PN, Lourens CW, Guthrie AJ. (2015) Equine encephalosis in Thoroughbred foals on a South African stud farm. Onderstepoort J Vet Res.;82(1):966. Abstract Thoroughbred foal body temperature data were collected from shortly after birth until shortly after weaning during the 2007/2008 season on a stud farm in the Western Cape Province of South Africa. Equine encephalosis (EE) caused by EE virus (EEV) serotype 4 (EEV-4) occurred in the foal group during the first autumn after their birth (March and April 2008). A descriptive study was undertaken to provide data on the EEV maternal antibody status, the association between pyrexia and EEV infection, and the incidence of infection amongst the foals prior to and during the episode. This included the frequent capturing of foal body temperature data and regular collection of serum and whole blood during pyretic episodes. Infection by EEV was determined using both virological and serological methods. A high EE incidence of at least 94% occurred amongst the foal cohort, despite the fact that 37% of foals had previously shown maternal antibody to EEV-4. Pyrexia in foals was not directly associated with EE infection and 41% of infected foals showed no detectable pyretic episode. Information obtained from this EE episode showed the high incidence of EEV infection in foals during the first autumn after their birth. Monitoring foal body temperature can alert farmers to outbreaks of infectious disease, such as EE. These results are relevant to the epidemiology of EE and facilitate greater understanding of it as a differential diagnosis of African horse sickness (AHS), given that EE and AHS have similar epidemiologic profiles.

173 Issel CJ, Foil LD. (2015) Equine infectious anaemia and mechanical transmission: man and the wee beasties. Rev Sci Tech.;34(2):513-23. Abstract There is no credible evidence that the lentivirus that causes equine infectious anaemia (EIA) replicates in invertebrates. The virus persistently infects its equid hosts and is often present in blood in significant quantities. Blood-feeding arthropods thus have the potential to transfer the virus between hosts, especially if their feeding on the first host is interrupted and immediately continued on a second host. The general details and dynamics of mechanical transmission are included in this paper, as this agent presents an excellent model. Mechanical transmission can be effectively controlled if the dynamics and interactions of the host, virus and vector populations are understood. Efficient transmission is proportional to the amount of agent found in the source material, the environmental survival of the agent, the number of vector feedings, the number of interrupted feedings, vector refeeding, the proximity of infected and naive hosts, host population density, and the length of time during which vectors and hosts are in contact. Establishing firm quantitative risk estimates for EIA is impossible, mainly because the virus content in blood can change exponentially from day to day. The EIA virus can be transmitted by horse flies for at least 30 minutes after feeding on a horse with acute signs of EIA, but the probability of a horse fly being interrupted and completing its blood feeding on a second host at a distance of 50 m is very low, and the separation of infected and uninfected equids by 200 m breaks transmission. The statements above assume that human interactions arenabsent or do not contribute to the risk of virus transmission; however, the risk from human interventions, such as the too-often-used procedure of administering >200 ml of plasma to foals, can easily be more than 107 times greater than the risk posed by a single horse fly. Controlling EIA depends upon the identification of persistently infected equids by serological testing because other methods of identifying infective virus or viral genetic material are less accurate or impractical

174 van Kasteren, Puck B., et.al. (2015) In vivo assessment of equine arteritis virus vaccine improvement by disabling the deubiquitinase activity of papain-like protease 2. Vet Mic, 178: 132–137 Abstract Arteriviruses are a family of positive-stranded RNA viruses that includes the prototypic equine arteritis virus (EAV) and porcine reproductive and respiratory syndrome virus (PRRSV). Although several vaccines against these viruses are commercially available there is room for improvement, especially in the case of PRRSV. The ability of arteriviruses to counteract the immune response is thought to decrease the efficacy of the current modified live virus vaccines. We have recently shown that the deubiquitinase (DUB) activity of EAV papain- like protease 2 (PLP2) is important for the inhibition of innate immune activation during infection. A vaccine virus lacking PLP2 DUB activity may therefore be more immunogenic and provide improved protection against subsequent challenge than its DUB-competent counterpart. To test this hypothesis, twenty Shetland mares were randomly assigned to one of three groups. Two groups were vaccinated, either with DUB-positive (n = 9) or DUB-negative (n = 9) recombinant EAV. The third group (n = 2) was not vaccinated. All horses were subsequently challenged with the virulent KY84 strain of EAV. Both vaccine viruses proved to be replication competent in vivo. In addition, the DUB-negative virus provided a similar degree of protection against clinical disease as its DUB-positive parental counterpart. Owing to the already high level of protection provided by the parental virus, a possible improvement due to inactivation of PLP2 DUB activity could not be detected under these experimental conditions. Taken together, the data obtained in this study warrant further in vivo investigations into the potential of using DUB-mutant viruses for the improvement of arterivirus vaccines. 175 Khatibzadeh, Sarah M., et.al. (2015) West Nile virus–specific immunoglobulin isotype responses in vaccinated and infected horses. Am J Vet Res;76:92–100. Abstract West Nile virus is a single-stranded RNA virus of the family Flaviviridae that has been endemic in North America since 1999.1 It is maintained in an enzootic cycle between avian and mosquito hosts, with Culex mosquitoes being the primary vector in North America.2 The virus can be transmitted by infected mosquitos to other animal species, including horses and humans. Most mammals are dead-end hosts of the virus and do not further transmit the infection. Clinical signs of WNV infection are manifested after a 5- to 15-day incubation period and low, transient viremia. In horses, WNV infection is most often subclinical. Occasionally, infected horses are mildly febrile and lethargic. The neurologic form of WNV disease in horses is caused by highly virulent strains of the virus, including certain lineage 1 strains in North America and a few lineage 2 strains in South Africa.3 Affected horsesdevelop meningoencephalitis and may have ataxia, tetraparesis, muscle fasciculations, fever, bruxism, blindness, and facial or lingual paralysis. The case fatality rate of the neurologic form of WNV disease in horses ranges from 30% to 40%.4–6

176 Kim, EJ,et.al. (2015) Antibody responses after vaccination against equine influenza in the Republic of Korea in 2013. J Vet Med Sci.;77(11):1517-21. Abstract In this study, antibody responses after equine influenza vaccination were investigated among 1,098 horses in Korea using the hemagglutination inhibition (HI) assay. The equine influenza viruses, A/equine/South Africa/ 4/03 (H3N8) and A/equine/Wildeshausen/1/08 (H3N8), were used as antigens in the HI assay. The mean seropositive rates were 91.7% (geometric mean antibody levels (GMT), 56.8) and 93.6% (GMT, 105.2) for A/equine/South Africa/4/03 and A/equine/Wildeshausen/1/08, respectively. Yearlings and two-year-olds in training exhibited lower positive rates (68.1% (GMT, 14) and 61.7% (GMT, 11.9), respectively, with different antigens) than average. Horses two years old or younger may require more attention in vaccination against equine influenza according to the vaccination regime, because they could be a target of the equine influenza virus 177 Korn A, et.al. (2015) Differential Gene Expression Profiles and Selected Cytokine Protein Analysis of Mediastinal Lymph Nodes of Horses with Chronic Recurrent Airway Obstruction (RAO) Support an Interleukin-17 Immune Response. PLoS One.;10(11):e0142622. Abstract Recurrent airway obstruction (RAO) is a pulmonary inflammatory condition that afflicts certain mature horses exposed to organic dust particulates in hay. Its clinical and pathological features, manifested by reversible bronchoconstriction, excessive mucus production and airway neutrophilia, resemble the pulmonary alterations that occur in agricultural workers with occupational asthma. The immunological basis of RAO remains uncertain although its chronicity, its localization to a mucosal surface and its domination by a neutrophilic, nonseptic inflammatory response, suggest involvement of Interleukin-17 (IL-17). We examined global gene expression profiles in mediastinal (pulmonary-draining) lymph nodes isolated from RAO-affected and control horses. Differential expression of > 200 genes, coupled with network analysis, supports an IL-17 response centered about NF-κB. Immunohistochemical analysis of mediastinal lymph node sections demonstrated increased IL-17 staining intensity in diseased horses. This result, along with the finding of increased IL-17 concentrations in lymph node homogenates from RAO-affected horses (P = 0.1) and a down-regulation of IL-4 gene and protein expression, provides additional evidence of the involvement of IL-17 in the chronic stages of RAO. Additional investigations are needed to ascertain the cellular source of IL-17 in this equine model of occupational asthma. Understanding the immunopathogenesis of this disorder likely will enhance the development of therapeutic interventions beneficial to human and animal pulmonary health.

178 Kumar S,et.al. (2015) Diagnostic application of recombinant equine merozoite surface antigen-1 in elisa for detection of Theileria equi specific antibodies. Jpn J Vet Res.;63(3):129-37. Abstract Theileria equi merozoite surface antigens have been an important candidate for development of diagnostics. We developed ELISA based on EMA-1 recombinant antigen, so as to widen our diagnostic confidence in detection of antibodies against T. equi in serosurveillance studies. The 547 bp EMA-1 gene fragment encoding high hydrophilic antigenic region was expressed with glutathione-S-transferase tag in prokaryotic system and purified protein (43 kDa) was used for development of ELISA (EMA-1t/ELISA). The EMA-1t/ELISA clearly differentiated T. equi-infected from Babesia caballi-infected horse sera or normal horse sera. The results of the study were validated with previously developed EMA-2ELISA on serum samples of known T. equi infection status and a very high correlation (0.93) was recorded between the relative percent positivity (RPP) values. Further diagnostic sensitivity of EMA-1t/ELISA was 0.92 while specificity was 1.0, indicating its suitability for sero-epidemiological studies. This assay was applied on serum samples (n ＝ 240) collected from field horses in northern part of India. High sero-prevalence of T. equi antibodies were diagnosed in serum samples collected from Haryana state (74%) and Uttarakhand state (36.31%). Results of this study suggested that the 43 kDa EMA-1 expressed protein could be a reliable immunodiagnostic antigen in ELISA for T. equi sero-prevalence studies

179 Laval K,et.al. (2015) Equine Herpesvirus Type 1 Enhances Viral Replication in CD172a+ Monocytic Cells upon Adhesion to Endothelial Cells. J Virol.;89(21):10912-23. Abstract Equine herpesvirus type 1 (EHV-1) is a main cause of respiratory disease, abortion and encephalomyelopathy in horses. Monocytic cells (CD172a+) are the main carrier cells of EHV-1 during primary infection and are proposed to serve as a ‘Trojan horse’ to facilitate the dissemination of EHV-1 to target organs. However, the mechanism by which EHV-1 is transferred from CD172a+ cells to endothelial cells (EC) remains unclear. The aim of this study was to investigate EHV-1 transmission between these two cell types. We hypothesized that EHV-1 employs specific strategies to promote the adhesion of infected CD172a+ cells to EC to facilitate EHV- 1 spread. Here we demonstrated that EHV-1 infection of CD172a+ cells resulted in a 3 to 5-fold increase in adhesion to EC. Antibody-blocking experiments indicated that α4β1, αLβ2 and αVβ3 integrins mediated adhesion of infected CD172a+ cells to EC. We showed that integrin-mediated PI(3)K and ERK/MAPK signaling pathways were involved in EHV-1-induced CD172a+ cell adhesion at early time of infection. EHV-1 replication was enhanced in adherent CD172a+ cells, which correlates with the production of TNF-α. In the presence of neutralizing antibodies, approximately 20% of infected CD172a+ cells transferred cytoplasmic material to uninfected EC and 0.01% of infected CD172a+ cells transmitted infectious virus to neighbouring cells. Our results demonstrated that EHV-1 infection induces adhesion of CD172a+ cells to EC, which enhances viral replication, but that transfer of viral material from CD172a+ cells to EC is a very specific and rare event. These findings give new insights in the complex pathogenesis of EHV1

180 Liu, A, Zhang J, Zhao J, Zhao W, Wang R, Zhang L. (2015) The first report of Cryptosporidium andersoni in horses with diarrhea and multilocus subtype analysis. Parasit Vectors.;8:483. Abstract Background: Horses interact with humans in a wide variety of sport competitions and non-competitive recreational pursuits as well as in working activities. Cryptosporidium spp are one of the most important zoonotic pathogens causing diarrhea of humans and animals. The reports of Cryptosporidium in horses and the findings of zoonotic Cryptosporidium species/genotypes show a necessity to carry out molecular identification of Cryptosporidium in horses, especially in diarrheic ones. The aim of the present study was to understand Cryptosporidium infection and species/genotypes in diarrheic horses, and to trace the source of infection of horse-derived Cryptosporidium isolates at a subtype level. Findings: Fecal specimens of 29 diarrheic adult horses were collected in Taikang County in northeastern China’s Heilongjiang Province. Cryptosporidium oocysts were concentrated by Sheather’s sugar flotation technique, and then examined by a bright-field microscope. Meanwhile, all the specimens were subjected to PCR amplification of the small subunit (SSU) rRNA gene of Cryptosporidium. C. andersoni isolates were further subtyped by multilocus sequence typing (MLST) at the four microsatellite/minisatellite loci (MS1, MS2, MS3 and MS16). One and two Cryptosporidium-positive isolates were obtained in horses by microscopy and by PCR, respectively. The two C. andersoni isolates were identified by sequencing of the SSU rRNA gene of Cryptosporidium. Both of them were identical to each other at the MS1, MS2, MS3 and MS16 loci, and MLST subtype A4,A4,A4,A1 was found here. Conclusions: This is the first report of C. andersoni in horses. The fact that the MLST subtype A4,A4,A4,A1 was reported in cattle suggests a large possibility of transmission of C. andersoni between cattle and horses

181 van Loon JP, Van Dierendonck MC. (2015) Monitoring acute equine visceral pain with the Equine Utrecht University Scale for Composite Pain Assessment (EQUUS-COMPASS) and the Equine Utrecht University Scale for Facial Assessment of Pain(EQUUS-FAP): A scale-construction study. Vet J.;206(3):356-64 Abstract Although recognition of equine pain has been studied extensively over the past decades there is still need for improvement in objective identification of pain in horses with acute colic. This study describes scale construction and clinical applicability of the Equine Utrecht University Scale for Composite Pain Assessment (EQUUS-COMPASS) and the Equine Utrecht University Scale for Facial Assessment of Pain (EQUUSFAP) in horses with acute colic. A cohort follow-up study was performed using 50 adult horses (n = 25 with acute colic, n = 25 controls). Composite pain scores were assessed by direct observations, Visual Analog Scale (VAS) scores were assessed from video clips. Colic patients were assessed at arrival, and on the first and second mornings after arrival. Both the EQUUS-COMPASS and EQUUS-FAP scores showed high inter- observer reliability (ICC = 0.98 for EQUUS-COMPASS, ICC = 0.93 for EQUUS-FAP, P < 0.001), while a moderate inter-observer reliability for the VAS scores was found (ICC = 0.63, P < 0.001). The cut-off value for differentiation between healthy and colic horses for the EQUUS-COMPASS was 5, and for differentiation between conservatively treated and surgically treated or euthanased patients itwas 11. For the EQUUSFAP, cut-off values were 4 and 6, respectively. Internal sensitivity and specificity were good for both EQUUS- COMPASS (sensitivity 95.8%, specificity 84.0%) and EQUUS-FAP (sensitivity 87.5%, specificity 88.0%). The use of the EQUUS-COMPASS and EQUUSFAP enabled repeated and objective scoring of pain in horses with acute colic. A follow-up study with new patients and control animals will be performed to further validate the constructed scales that are described in this study.

182 Maddox TW, et.al. (2015) Antimicrobial resistance in bacteria from horses: Epidemiology of antimicrobial resistance. Equine Vet J.;47(6):756-65. Abstract Antimicrobial resistance poses a significant threat to the continued successful use of antimicrobial agents for the treatment of bacterial infections. While the epidemiology of antimicrobial resistance in bacteria from man has been studied extensively, less work has been undertaken in companion animals, particularly horses. Methicillin-resistant Staphylococcus aureus has been identified as a cause of infections, with a low prevalence of nasal carriage by horses in the community but higher for hospitalised horses. Molecular characterisation has shown methicillinresistant Staphylococcus aureus strains either to be predominantly of types associated with horses or of sequence type ST398. Antimicrobialresistant Escherichia coli (including multidrug-resistant and extended spectrum b-lactamase-producing isolates) have caused infections and been documented in faecal carriage by horses, with many significant resistance mechanisms identified. More sporadic reports and molecular characterisation exist for resistance in other bacteria such as enterococci, Salmonella, Acinetobacter and Pseudomonas species. Limited work has been undertaken evaluating risk factors and much of the epidemiology of antimicrobial resistance in bacteria from horses remains to be determined.

183 Marr CM. (2015) The Equine Neonatal Cardiovascular System in Health and Disease. Vet Clin North Am Equine Pract.;31(3):545-65. Abstract The neonatal foal is in a transitional state from prenatal to postnatal circulation, and cardiac murmurs are common in neonates because of the flow through shunts. Dysrhythmias are present in many foals shortly after birth, but these are usually transient and of little clinical significance. The neonatal foal is prone to infection and cardiac trauma, both of which may require intensive monitoring and therapy. Echocardiography is the main tool used for valuation of the cardiovascular system, although angiography, nuclear scintigraphy, and computed tomography have important roles. Congenital disease represents an interesting diagnostic challenge for the neonatologist, but surgical correction is not appropriate for most equids.

184 Marth CD,et.al. (2015) Deep sequencing of the uterine immune response to bacteria during the equine oestrous cycle. BMC Genomics.;16:934. Abstract Background: The steroid hormone environment in healthy horses seems to have a significant impact on the efficiency of their uterine immune response. The objective of this study was to characterize the changes in gene expression in the equine endometrium in response to the introduction of bacterial pathogens and the influence of steroid hormone concentrations on this expression. Methods: Endometrial biopsies were collected from five horses before and 3 h after the inoculation of Escherichia coli once in oestrus (follicle >35 mm in diameter) and once in dioestrus (5 days after ovulation) and analysed using high-throughput RNA sequencing techniques (RNA-Seq). Results: Comparison between time points revealed that 2422 genes were expressed at significantly higher levels and 2191 genes at significantly lower levels 3 h post inoculation in oestrus in comparison to pre- inoculation levels. In dioestrus, the expression of 1476 genes was up-regulated and 383 genes were down- regulated post inoculation. Many immune related genes were found to be up-regulated after the introduction of E. coli. These include pathogen recognition receptors, particularly toll-like receptors TLR2 and 4 and NOD-like receptor NLRC5. In addition, several interleukins including IL1B, IL6, IL8 and IL1ra were significantly up- regulated. Genes for chemokines, including CCL 2, CXCL 6, 9, 10, 11 and 16 and those for antimicrobial peptides, including secretory phospholipase sPLA2, lipocalin 2, lysozyme and equine β-defensin 1, as well as the gene for tissue inhibitor for metalloproteinases TIMP-1 were also up-regulated post inoculation. Conclusion: The results of this study emphasize the complexity of an effective uterine immune response during acute endometritis and the tight balance between pro- and anti-inflammatory factors required for efficient elimination of bacteria. It is one of the first high-throughput analyses of the uterine inflammatory response in any species and several new potential targets for treatment of inflammatory diseases of the equine uterus have been identified.

185 Martínez-Valladares M,et.al. (2015) Resistance of gastrointestinal nematodes to the most commonly used anthelmintics in sheep, cattle and horses in Spain. Vet Parasitol.;211(3-4):228-33. Abstract The objective of this study was to evaluate the status of anthelmintic resistance (AR) in ruminants and horses in Spain. The efficacy of commonly used macrocyclic lactones (MLs) - ivermectin (IVM) and moxidectin (MOX) - was measured in sheep, cattle and horses. In addition, albendazole (ABZ) and levamisole (LEV) were evaluated in sheep and oxibendazole (OXI) and pyrantel (PYR) in horses. Efficacy was evaluated based on the difference between the arithmetic mean pre-and post-treatment faecal egg count (in cattle and horses), or compared to an untreated control group (in sheep). AR was present when the percentage reduction in egg count was <95% and the lower 95% confidence interval (CI) was <90%; if only one of these two criteria was met, the finding was recorded as suspected AR (SAR). In horses, AR to PYR and OXI was considered when the percentage reduction in egg count was ≤90% and the lower 95% CI was ≤80%. For each animal species, at least 10 study sites were selected. AR to at least one of the drugs was detected in all 10 sheep flocks; the main parasite identified after treatment was Teladorsagia circumcincta. Moreover, in 5 flocks multidrug resistance was identified, on 4 farms to drugs from different families, on one farm to both MOX and IVM and on another farm to all drugs tested. In cattle, the efficacy of both MOX and IVM was 100% on 4 and 3 farms, respectively, and therefore 60% of these farms were considered to have AR or SAR to both MLs. The most frequent parasite identified after treatment was Trichostrongylus spp., although Ostertagia ostertagi was also identified after treatment on one farm. In contrast to ruminants, the 4 drugs evaluated in horses were highly efficacious against strongyles, with efficacies for the MLs and OXI between 95 and 100% and between 94 and 100% for PYR, although 3 herds were SAR against PYR. In conclusion, AR to at least one of the commonly used drugs was identified on all sheep flocks investigated in the northwest of Spain. The occurrence of AR to MLs in cattle was higher than expected but consistent with what was observed in sheep. In horses, all currently used drugs were confirmed as effective against strongyles

186 McClure SR, Koenig R, Hawkins PA. (2015) A randomized controlled field trial of a novel trimethoprim-sulfadiazine oral suspension for treatment of Streptococcus equi subsp zooepidemicus infection of the lower respiratory tract in horses. J Am Vet Med Assoc.;246(12): 1345-53. Abstract Horses with lower respiratory tract infections caused by S equi subsp zooepidemicus were treated with a new formulation of combined trimethoprim-sulfadiazine oral suspension at a dosage of 24 mg/kg (10.9 mg/lb) twice daily for 10 days (treatment group) or with an equivalent volume of saline (0.9% NaCl) solution (placebo group). Response to treatment, including clinical signs and fecal consistency scores, was assessed twice daily. Any adverse effects were recorded. The primary outcome variable was clinical response; the secondary outcome variable was eradication of S equi subsp zooepidemicus on study day 17 as determined by bacteriologic culture of repeated transtracheal-wash specimens. Results—Of the 119 horses allocated to the treatment group, 69 (58%) had a positive clinical response. A significantly smaller proportion of horses in the placebo group (9/61 [15%]) had a positive clinical response. By day 5, 25 of 61 (41%) placebo horses had been withdrawn from the study because of negative clinical response, compared with only 10 of 119 (8.4%) treated horses. By day 10, 28 of 61 (46%) placebo horses had been withdrawn because of negative clinical response, compared with only 13 of 119 (11%) treated horses. There were few adverse events associated with the trimethoprim-sulfadiazine suspension. There were no significant differences in fecal consistency scores between treatment and placebo groups.

187 Méndez-López, MR, et.al. (2015) Association of vectors and environmental conditions during the emergence of Peruvian horse sickness orbivirus and Yunnan orbivirus in northern Peru. J Vector Ecol.;40(2):355-63. Abstract Since 1983, cases of diseased donkeys and horses with symptoms similar to those produced by alphaviruses were identified in two departments in northern Peru; however serological testing ruled out the presence of those viruses and attempts to isolate an agent were also unproductive. In 1997, also in northern Peru, two new orbiviruses were discovered, each recognized as a causative agent of neurological diseases in livestock and domestic animals and, at the same time, mosquitoes were found to be infected with these viruses. Peruvian horse sickness virus (PHSV) was isolated from pools of culicid mosquitoes, Aedes serratus and Psorophora ferox, and Yunnan virus (YUOV) was isolated from Aedes scapularis in the subtropical jungle (upper jungle) located on the slope between the east side of the Andes and the Amazonian basin in the Department of San Martín. Both viruses later were recovered from mosquitoes collected above the slope between the west side of the Andes and the coast (Department of Piura) in humid subtropical areas associated with the Piura River basin. In this region, PHSV was isolated from Anopheles albimanus and YUOV was isolated from Ae. scapularis. We discuss the ecology of vector mosquitoes during the outbreaks in the areas where these mosquitoes were found.

188 Molaei G, et.al. (2015) Insights into the recent emergence and expansion of eastern equine encephalitis virus in a new focus in the Northern New England USA. Parasit Vectors.;8:516. Abstract Background: Eastern equine encephalomyelitis virus (EEEV) causes a highly pathogenic zoonosis that circulates in an enzootic cycle involving the ornithophagic mosquito, Culiseta melanura, and wild passerine birds in freshwater hardwood swamps in the northeastern U.S. Epidemic/epizootic transmission to humans/ equines typically occurs towards the end of the transmission season and is generally assumed to be mediated by locally abundant and contiguous mammalophagic “bridge vector” mosquitoes. Methods: Engorged mosquitoes were collected using CDC light, resting box, and gravid traps during epidemic transmission of EEEV in 2012 in Addison and Rutland counties, Vermont. Mosquitoes were identified to species and blood meal analysis performed by sequencing mitochondrial cytochrome b gene polymerase chain reaction products. Infection status with EEEV in mosquitoes was determined using cell culture and RT-PCR assays, and all viral isolates were sequenced and compared to other EEEV strains by phylogenetic analysis. Results: The host choices of 574 engorged mosquitoes were as follows: Cs. melanura (n = 331, 94.3 % avian-derived, 5.7 % mammalian- derived); Anopheles quadrimaculatus (n = 164, 3.0 % avian, 97.0 % mammalian); An. Punctipennis (n = 56, 7.2 % avian, 92.8 % mammalian), Aedes vexans (n = 9, 22.2 % avian, 77.8 % mammalian); Culex pipiens s.l. n = 6, 100 % avian); Coquillettidia perturbans (n = 4, 25.0 % avian, 75.0 % mammalian); and Cs. morsitans (n = 4, 100 % avian). A seasonal shift in blood feeding by Cs. melanura from Green Heron towards other avian species was observed. EEEV was successfully isolated from blood-fed Cs. melanura and analyzed by phylogenetic analysis. Vermont strains from 2012 clustered with viral strains previously isolated in Virginia yet were genetically distinct from an earlier EEEV isolate from Vermont during 2011. Conclusions: Culiseta melanura acquired blood meals primarily from birds and focused feeding activity on several competent species capable of supporting EEEV transmission. Culiseta melanura also occasionally obtained blood meals from mammalian hosts including humans. This mosquito species serves as the primary vector of EEEV among wild bird species, but also is capable of occasionally contributing to epidemic/epizootic transmission of EEEV to humans/equines. Other mosquito species including Cq. perturbans that feed more opportunistically on both avian and mammalian hosts may be important in epidemic/epizootic transmission under certain conditions. Phylogenetic analyses suggest that EEEV was independently introduced into Vermont on at least two separate occasions 189 Molaei G,et.al. (2015) Vector-Host Interactions of Culiseta melanura in a Focus of Eastern Equine Encephalitis Virus Activity in Southeastern Virginia. PLoS One.;10(9):e0136743. Abstract Eastern equine encephalitis virus (EEEV) causes a highly pathogenic mosquito-borne zoonosis that is responsible for sporadic outbreaks of severe illness in humans and equines in the eastern USA. Culiseta (Cs.) melanura is the primary vector of EEEV in most geographic regions but its feeding patterns on specific avian and mammalian hosts are largely unknown in the mid-Atlantic region. The objectives of our study were to: 1) identify avian hosts of Cs. melanura and evaluate their potential role in enzootic amplification of EEEV, 2) assess spatial and temporal patterns of virus activity during a season of intense virus transmission, and 3) investigate the potential role of Cs. melanura in epidemic/epizootic transmission of EEEV to humans and equines. Accordingly, we collected mosquitoes at 55 sites in Suffolk, Virginia in 2013, and identified the source of blood meals in engorged mosquitoes by nucleotide sequencing PCR products of the mitochondrial cytochrome b gene. We also examined field-collected mosquitoes for evidence of infection with EEEV using Vector Test, cell culture, and PCR. Analysis of 188 engorged Cs. melanura sampled from April through October 2013 indicated that 95.2%, 4.3%, and 0.5% obtained blood meals from avian, mammalian, and reptilian hosts, respectively. American Robin was the most frequently identified host for Cs. melanura (42.6% of blood meals) followed by Northern Cardinal (16.0%), European Starling (11.2%), Carolina Wren (4.3%), and Common Grackle (4.3%). EEEV was detected in 106 mosquito pools of Cs. melanura, and the number of virus positive pools peaked in late July with 22 positive pools and a Maximum Likelihood Estimation (MLE) infection rate of 4.46 per 1,000 mosquitoes. Our findings highlight the importance of Cs. melanura as a regional EEEV vector based on frequent feeding on virus-competent bird species. A small proportion of blood meals acquired from mammalian hosts suggests the possibility that this species may occasionally contribute to epidemic/epizootic transmission of EEEV

190 Nemoto, M, et.al. (2015) Low prevalence of equine coronavirus in foals in the largest thoroughbred horse breeding region of Japan, 2012-2014. Acta Vet Scand.;57:53. Abstract Background: Equine coronavirus (ECoV) is considered to be a diarrheic pathogen in foals. In central Kentucky in the United States, it has been shown that approximately 30 % of thoroughbred foals are infected with ECoV and thus it is considered widely prevalent. In contrast, the epidemiology of ECoV and its relationship to diarrhea in foals are poorly understood in Japan. We investigated ECoV in rectal swabs collected from thoroughbred foals in Japan. Results: We collected 337 rectal swabs from 307 diarrheic foals in the Hidaka district of Hokkaido, the largest thoroughbred horse breeding region in Japan, between 2012 and 2014. In addition, 120 rectal swabs were collected from 120 healthy foals in 2012. These samples were tested by reverse transcription loop-mediated isothermal amplification and a real-time reverse transcription-polymerase chain reaction. All samples collected from diarrheic foals were negative, and only three samples (2.5 %) collected from healthy foals were positive for ECoV. Compared with central Kentucky, ECoV is not prevalent among thoroughbred foals in the Hidaka district of Hokkaido. Conclusion: ECoV is not prevalent and was not related to diarrhea in thoroughbred foals in the Hidaka district of Hokkaido between 2012 and 2014.

191 Niczyporuk JS, et.al. (2015) Occurrence of West Nile virus antibodies in wild birds, horses, and humans in Poland. Biomed Res Int. 2015;:234181. Abstract Serum samples of 474 wild birds, 378 horses, and 42 humans with meningitis and lymphocytic meningitis were collected between 2010 and 2014 from different areas of Poland. West Nile virus (WNV) antibodies were detected using competition enzyme linked immunosorbent assays: ELISA-1 ID ScreenWest Nile Competition, IDvet, ELISA-2 ID ScreenWest Nile IgM Capture, and ELISA-3 IngezimWest Nile Compac. The antibodies were found in 63 (13.29%) out of 474 wild bird serum samples and in one (0.26%) out of 378 horse serumsamples. Fourteen (33.33%) out of 42 sera from patients were positive againstWNV antigen and one serumwas doubtful. Positive samples obtained in birds were next retested with virus microneutralisation test to confirm positive results and cross-reactions with other antigens of the Japanese encephalitis complex. We suspect that positive serological results in humans, birds, and horses indicate that WNVcan be somehowclosely related with the ecosystem in Poland.

192 Passamonti, F., et.al. (2015) Rhodococcus equi pneumonia in foals: An assessment of the early diagnostic value of serum amyloid A and plasma fibrinogen concentrations in equine clinical practice. The Veterinary Journal. 203 211–218. Abstract Early diagnosis and prevention of Rhodococcus equi pneumonia in foals represent important goals for equine clinicians. Recent protocols for diagnosis and treatment of Rhodococcosis in foals typically rely on a multimodal approach based on sonographic evidence suggestive of pyogranulomas, sonographic abscess scores and laboratory findings including plasma fibrinogen concentrations, blood biochemistry testing and platelet and leukocyte counts. The aim of this study was to assess the utility of weekly testing of serum amyloid A (SAA) and plasma fibrinogen concentrations in foals to achieve early diagnosis of R. equi pneumonia prior to the onset of clinical signs. This testing was used to simulate a clinically practical screening procedure and compared with thoracic ultrasonography performed in parallel. The present study suggests that SAA does not represent a reliable early marker of Rhodococcosis when plasma concentrations are tested weekly. However, when clinical signs of R. equi pneumonia are present, SAA concentrations may allow clinicians to obtain ‘real-time’ indications concerning both the progress of infection and the effectiveness of therapy. This study raises the possibility that plasma fibrinogen monitoring starting at 1 week of age and repeated on a weekly basis, could serve as a screening test allowing clinicians to identify foals as suspected of R. equi infection. Future investigations regarding both physiological plasma fibrinogen concentrations in foals as well as fibrinogen kinetics in foals affected with R. equi pneumonia, including the establishment of appropriate reference intervals for the test method employed in this study, will be necessary in order to clarify this possibility. 193 Paştiu AI, et.al. (2015) Toxoplasma gondii in horse meat intended for human consumption in Romania. Vet Parasitol.;212(3-4):393-5. Abstract The prevalence of Toxoplasma gondii, an economically important zoonotic protozoan, was investigatedin horses slaughtered for export and human consumption in the North of Romania. Pairs of samples, seraand heart tissues, were collected from 82 slaughtered horses. Examination of horse sera by ELISA at adilution of 1:10, and by modified agglutination test (MAT) at a dilution of 1:6, revealed that 32 (39%)and 31(37.8%) horses, respectively, had antibodies against T. gondii. Using polymerase chain reaction(PCR) analysis, T. gondii DNA was not found in any heart sample collected from horses. By bioassay inmice, we obtained viable isolates of T. gondii from two of ten horses determined to be strongly positiveby serological assay/ELISA. The prevalence estimated in horses highlighted the potential risk for humancontamination by consumption of raw or undercooked meat.

194 Pavulraj S, Bera BC, et.al. (2015) Pathology of Equine Influenza virus (H3N8) in Murine Model. PLoS One.;10(11):e0143094. Abstract Equine influenza viruses (EIV) - H3N8 continue to circulate in equine population throughout the world. They evolve by the process of antigenic drift that leads to substantial change in the antigenicity of the virus, thereby necessitating substitution of virus strain in the vaccines. This requires frequent testing of the new vaccines in the in vivo system; however, lack of an appropriate laboratory animal challenge model for testing protective efficacy of equine influ- enza vaccine candidates hinders the screening of new vaccines and other therapeutic approaches. In the present investigation, BALB/c mouse were explored for suitability for conducting pathogenecity studies for EIV. The BALB/c mice were inoculated intranasally @ 2×10 6.24 EID 50 with EIV (H3N8) belonging to Clade 2 of Florida sublineage and monitored for setting up of infection and associated parameters. All mice inoculated with EIV exhibited clinical signs viz. loss in body weights, lethargy, dyspnea, etc, between 3 and 5 days which commensurate with lesions observed in the respiratory tract including rhinitis, tracheitis, bronchitis, bronchiolitis, alveolitis and diffuse interstitial pneumonia. Transmission electron microscopy, immunohistochemistry, virus quantification through titration and qRT-PCR demonstrated active viral infection in the upper and lower respiratory tract. Serology revealed rise in serum lactate dehydrogenase levels along with sero-conversion. The pat-tern of disease progression, pathological lesions and virus recovery from nasal washings and lungs in the present investigations in mice were comparable to natural and experimen- tal EIV infection in equines. The findings establish BALB/c mice as small animal model for studying EIV (H3N8) infection and will have immense potential for dissecting viral pathogen- esis, vaccine efficacy studies, preliminary screening of vaccine candidates and antiviral therapeutics against EIV

195 Razzaq F, et.al. (2015) Prevalence of Anaplasma phagocytophilum in horses from Southern Punjab (Pakistan). Trop BiomedJun;32(2):233-9. Abstract The present study was designed to optimize a PCR-RFLP protocol for the molecular detection of Anaplasma sp. and to compare its prevalence in blood samples of equines from Southern Punjab (Pakistan) and to find out the risk factors involved in the spread of anaplasmosis. A total of 210 blood samples were collected from equines from 2 sampling sites (Dera Ghazi Khan and Khanewal districts). Data on the animals’ characteristics (age, species and gender) were collected through survey. PCR amplified the 577bp product specific for 16S rRNA gene of Anaplasma spp. in 9 blood samples (4.3% of total), [Dera Ghazi Khan (N = 3) and Khanewal (N = 6)]. These Anaplasma spp. positive blood samples were used for PCR amplification using A. phagocytophilum specific primers and parasite was detected in all of them. Also it was revealed that the characteristics of the animals i.e. age, gender, species had no significant association with the presence of Anaplasma sp. Hematological parameters remained unaffected while lymphocyte count was significantly lowered in A. Phagocytophilum positive samples.

196 Revold, T, et.al. (2015) Sørum H. Listeria monocytogenes associated kerato-conjunctivitis in four horses in Norway. Acta Vet Scand.;57:76. Abstract Listeria monocytogenes has been reported to cause various infectious diseases in both humans and animals. More rarely, ocular infections have been reported. To our knowledge, only two cases of Listeria keratitis have been described in horses. We report kerato-conjunctivitis in four Norwegian horses associated with L. monocytogenes. Clinically, all cases were presented with recurrent unilateral kerato-conjunctivitis. L. monocytogenes bacteria were isolated from swab samples from all cases, and cytology carried out in 3 cases was indicative of L. monocytogenes infection. The present report describes the first known cases in which L. monocytogenes has been isolated from keratitic lesions in horses in Norway. A potential risk factor may be feeding of silage or haylage, but other sources of infection cannot be ruled out. The phenotypic features including antimicrobial susceptibility and serotype of the isolates are described. Laboratory detection of L. monocytogenes demands extra caution since only low numbers of bacteria were detected in the eye-swabs, probably due to the low volume of sample material and the intracellular niche of the bacterium. A general poor response to treatment in all these cases indicates that clinicians should pay extra attention to intensity and duration of treatment if L. monocytogenes is identified in connection with equine kerato-conjunctivitis.

197 Robin M, Archer D, McGowan C, Garros C, Gardès L, Baylis M. (2015) Repellent effect of topical deltamethrin on blood feeding by Culicoides on horses. Vet Rec.;176(22):574. Abstract African horse sickness (AHS) is a vectorborne disease spread by Culicoides biting midges. The UK’s Department for Environment, Food and Rural Affairs currently suggests using topical deltamethrin for AHS control; however, no data are available regarding its efficacy in the horse. The aims of this study were to investigate the effect of topical deltamethrin on blood feeding by Culicoides on horses and to investigate which Culicoides species blood fed on horses. Three pairs of horses were placed in partially enclosed cages that allowed samples representing the Culicoides interacting with individual horses to be sampled. Four data collection sessions were completed before one horse from each pair was topically treated with 10 ml of 1 per cent deltamethrin solution and another four sessions were then carried out. Collected Culicoides were identified and each biting midge examined to see if it had blood fed. The most abundant species collected were C. chiopterus, C. dewulfi, C. Obsoletus and C. scoticus (44.3 per cent) and either C. pulicaris or C. punctatus (34.7 per cent). These species were also more likely to have blood fed than other species, supporting their potential role as AHS vectors if the virus were to reach the UK. There was no significant effect of treatment on blood feeding by Culicoides. The results do not support the use of topical deltamethrin to prevent blood feeding by Culicoides on individual horses; however, the study does not investigate the effect that the widespread use of topical deltamethrin might have on vector numbers or disease transmission from viraemic individuals during an outbreak of AHS.

198 Saey V, Famaey N, et.al. (2015) Biomechanical and biochemical properties of the thoracic aorta in warmblood horses, Friesian horses, and Friesians with aortic rupture. BMC Vet Res.;11:285. Abstract Background: Thoracic aortic rupture and aortopulmonary fistulation are rare conditions in horses. It mainly affects Friesian horses. Intrinsic differences in biomechanical properties of the aortic wall might predispose this breed. The biomechanical and biochemical properties of the thoracic aorta were characterized in warmblood horses, unaffected Friesian horses and Friesians with aortic rupture in an attempt to unravel the underlying pathogenesis of aortic rupture in Friesian horses. Samples of the thoracic aorta at the ligamentum arteriosum (LA), mid thoracic aorta (T1) and distal thoracic aorta (T2) were obtained from Friesian horses with aortic rupture (A), nonaffected Friesian (NA) and warmblood horses (WB). The biomechanical properties of these samples were determined using uniaxial tensile and rupture assays. The percentages of collagen and elastin (mg/mg dry weight) were quantified. Results: Data revealed no significant biomechanical nor biochemical differences among the different groups of horses. The distal thoracic aorta displayed an increased stiffness associated with a higher collagen percentage in this area and a higher load-bearing capacity compared to the more proximal segments. Conclusions: Our findings match reported findings in other animal species. Study results did not provide evidence that the predisposition of the Friesian horse breed for aortic rupture can be attributed to altered biomechanical properties of the aortic wall.

199 Sarkar S, Balasuriya UB, Horohov DW, Chambers TM. (2015) Equine herpesvirus-1 suppresses type-I interferon induction in equine endothelial cells. Vet Immunol Immunopathol.;167: 122-9. Abstract Equine herpesvirus-1 (EHV-1) is one of the most common and important respiratory viral pathogens ofhorses. EHV-1 in horses replicates initially in the respiratory epithelium and then spreads systematicallyto endothelial cells lining the small blood vessels in the uterus and spinal cord, and highly pathogenicvirus strains can produce aborted fetuses or myeloencephalopathy. Like other herpes viruses, EHV-1employs a variety of mechanisms for immune evasion. Some herpes viruses down-regulate the type-Iinterferon (IFN) response to infection, but such activity has not been described for EHV-1. Here, in an invitro system utilizing an established equine endothelial cell line, we studied the temporal effect on IFN- _responses following infection with the neuropathogenic T953 strain of EHV-1. Results show that after anearly induction of IFN- _, the virus actively shut down further production of IFN- _ and this was correlatedwith expression of the viral late genes. Expression of the IFN response factor viperin, a marker of hostcell type-I IFN responses, was also suppressed by T953 virus infection. EHV-1-mediated suppression ofhost type-I IFN responses may play an important role in EHV-1 pathogen

200 Sasmitha, I. M. A, Ramona, Y, Yustiantara, P. S. Potensi Lactobacillus sp. Yang diisolasi dari sus kuda Sumbawa dalam mengontrol Candida albicans penyebab Kandidiasis. Jurusan Farmasi Fakultas Matematika Dan Ilmu Pengetahuan Alam Universitas Udayana. , Vol. 4 (2015) Abstract Kandidiasis merupakan penyakit infeksi yang disebabkan oleh Candida albicans. Sampai saat ini, pengobatan kandidiasis bergantung pada penggunaan antibiotik yang diperlakukan per oral atau topikal. Sebagai alternatif terapi, beberapa peneliti menyarankan penggunaan probiotik, sehingga penggunaan antibiotik dapat dikurangi. Penelitian ini dimulai dengan pengamatan aktivitas antagonis BAL (Bakteri asam laktat) terhadap C. albicans (agen penyebab Candidiasis) secara in vitro diikuti oleh elusidasi mekanisme yang dilakukan oleh BAL dalam menghambat C. albicans. Hasil penelitian menunjukkan bahwa tiga isolat BAL (Lactobacillus SMM 33, SMM 44, dan SMM 49) menghambat pertumbuhan C. albicans dalam dual culture assay dengan berbagai tingkat hambatan. Dalam uji-uji lebih lanjut, isolat Lactobacillus SMM 44, dan SMM 49 diketahui menghambat C. albicans melalui produksi bakteriosin. Uji susceptibility menunjukkan kedua isolat ini resisten terhadap metronidazol, Hal ini mengindikasikan bahwa kedua isolat tersebut dapat digunakan secara sinergis dengan antibiotik untuk terapi infeksi yang disebabkan oleh C. albicans.

201 Schellenbacher C,et.al. (2015) Establishment of an in vitro equine papillomavirus type 2 (EcPV2) neutralization assay and a VLP-based vaccine for protection of equids against EcPV2-associated genital tumors. Virology;486:284-90. Abstract The consistentandspecific presenceof Equus caballus papillomavirustype2(EcPV2)DNAandmRNAin equinegenitalsquamouscellcarcinoma(gSCC)issuggestiveofanetiologicalroleintumordevelopment. To further validatethisconcept,EcPV2-neutralizingserumantibodytitersweredeterminedbyan EcPV2 pseudovirion(PsV) neutralizationassay.Furthermore,anEcPV2L1virus-likeparticle(VLP)-based vaccine was generated anditsprophylactic efficacy evaluated in vivo. All 6/6gSCC-affected,butonly3/20tumor-freeage-matched animals revealed EcPV2-neutralizing serum antibody titers by PsVassay. Vaccination of NZW rabbits and BalbCmice with EcPV2L1VL Pusing Freund'soralumrespectivelyasadjuvantinducedhigh-titer neutralizing serum antibodies (1600– 12,800). PassivetransferwithrabbitEcPV2–VLP immuneseracompletelyprotectedmicefrom experimental vaginalEcPV2Ps Vinfection. These findings support the impact of EcPV2inequinegSCC development and recommendEcPV2L1 VLP asprophylacticvaccineagainstEcPV2 infection and associated disease in equids.

202 Schwartz EJ, Nanda S, Mealey RH. (2015) Antibody escape kinetics of equine infectious anemia virus infection of horses. J Virol.;89(13):6945-51. Abstract Lentivirus escape from neutralizing antibodies (NAbs) is not well understood. In this work, we quantified antibody escape of a lentivirus, using antibody escape data from horses infected with equine infectious anemia virus. We calculated antibody blocking rates of wild-type virus, fitness costs of mutant virus, and growth rates of both viruses. These quantitative kinetic estimates of antibody escape are important for understanding lentiviral control by antibody neutralization and in developing NAb-eliciting vaccine strategies.

203 Smith, MA, Nolan TJ, Rieger R, Aceto H, Levine DG, Nolen-Walston R, Smith BI. (2015) Efficacy of major anthelmintics for reduction of fecal shedding of strongyle-type eggs in horses in the Mid-Atlantic region of the United States. Vet Parasitol.;214(1-2):139-43. Abstract In the last decade there have been numerous reports of anthelmintic resistant cyathostomins in many parts of the world. The objective of the present study was to evaluate the efficacy of the commercially available anthelmintics against cyathostomin egg shedding in the Mid-Atlantic region of the United States. A total of 989 horses from 67 different farms located in southeastern Pennsylvania, northern Delaware, and northeastern Maryland were treated with fenbendazole, oxibendazole, pyrantel pamoate, ivermectin, or moxidectin at their recommended dosages. Fecal egg count reduction testing was used to determine the efficacy of each anthelmintic on those horses with fecal egg counts of ≥ 200 eggs per gram on the day of treatment (272 horses). Decreased efficacy (reduction of strongyle-type fecal egg counts by less than 90%) was found for fenbendazole, oxibendazole, and pyrantel pamoate, with only 6%, 21% and 43% of horses showing reductions of greater than 90%, respectively. The macrocyclic lactones showed high efficacy in all horses sampled in this study. The decreased anthelmintic efficacy detected in this study adds further evidence for the existence of resistant cyathostomins throughout much of the eastern United States. Findings from this study can be used to create a more sustainable approach for parasite control programs.

204 Socha, W., J. Rola, J.F. Żmudziński(2015), Variability of non-structural proteins of equine arteritis virus during persistent infection of the stallion. Polish J.of Vet Sci,. 18, No. 2: 255–259 Abstract The genetic stability of ORF1a encoding non-structural proteins nsp1, nsp2, nsp3 and nsp4 of equine arteritis virus (EAV) has been analysed for nearly seven years in a persistently infected stallion of the Malopolska breed. Between November 2004 and June 2011, 11 semen samples were collected. Viral RNA extracted from semen of this carrier stallion was amplified, sequenced and compared with the sequences of the other known strains of EAV. Sequence analysis of ORF1a showed 84 synonymous and 16 non-synonymous mutations. The most variable part of ORF1a was the region encoding nsp2 protein with 13 non-synonymous substitutions. The degree of amino acid identity between isolates ranged from 98.91 to 100%. Only single non-synonymous mutations were detected in nsp1 (one substitution) and nsp4 (two substitutions). The most stable was nsp3 in which no amino acid substitutions were observed during the whole period of observation.

205 Sokół R,et.al. ( 2015) Estimation of infection of internal parasites in horses from different type of farms. Ann Parasitol.;61(3):189-92. Abstract Studies were carried out in year 2014 during the pasture period (from April to October) in Warmia and Mazury Region. Fecal samples were taken from cold- and warmblood horses from individual and agrotouristic farms with the different housing, feeding and pasture- care practices. Total of 512 horses were examined (320 mares, 170 geldings and 22 stallions). In the group of 185 horses from individual farms, 119 animals (64.3%) were infected with gastro-intestinal parasites. Among the 372 horses from agrotouristic farms 169 (51.7%) were infected with parasites. Most of the animals expelled the eggs of Cyathostominae. In some individuals occurred eggs of Strongylus spp., Parascaris equorum, Strongyloides westeri and tapeworm of Anoplocephala. The number of infected horses from agrotouristic farms was lower than from individual farms, probably due to more regular deworming (usually 2 times a year) and bigger care paid to cleaning pastures.

206 Stasiak, K, Rola J, Zmudzinski JF. (2015) Application of real-time PCR for evaluation of distribution of equine herpesvirus type 1 in tissues of aborted fetuses. Pol J Vet Sci.;18(4):833-9. Abstract A highly sensitive and specific real-time PCR assay was used for detection and quantitation of equine herpesvirus type 1 (EHV-1) in the different internal organs of aborted fetuses. Tissue samples from 23 aborted fetuses submitted to the Department of Virology of the National Veterinary Research Institute in Pulawy between 2012 and 2013 were used for testing. Total DNA was extracted using a phenol-chloroform-isoamyl alcohol standard protocol. A real-time PCR with forward and reverse primers encompassing a highly conserved region encoding viral glycoprotein B was adapted for diagnosis of EHV-1 infection. The detection limit of the assay was shown to be 6.0x100 of viral DNA copies and the obtained standard curve exhibited a linear range from 100 to 107 molecules. Sixteen out of twenty three aborted fetuses (69.5%) were positive for EHV-1 in real-time PCR. The highest EHV-1 DNA load was obtained for liver (mean Ct value: 15.7) and lung (18.2) samples, while the lowest was in the thymus (29.6) and placenta (28.4).

207 Stasiak, K, et.al. (2015) Detection of the neuropathogenic variant of equine herpesvirus 1 associated with abortions in mares in Poland. BMC Vet Res.;11:102. Abstract Background: The incidence of reported cases of equine herpesvirus myeloencephalopathy (EHM) caused by infection with neuropathogenic strains of equine herpesvirus 1 (EHV-1) has markedly increased over the last decade in many Western countries. The purpose of this study was to estimate the prevalence of the neuropathogenic (G2254) and non-neuropathogenic (A2254) variants of EHV-1 among isolates associated with abortions in Polish stud farms. Results: The results of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing were consistent, and showed that two out of 64 abortions (3.1%) were induced by the neuropathogenic genotype G2254. All remaining 18 EHV-1 positive abortion cases (28.1%) were caused by the non-neuropathogenic genotype A2254. Conclusions: Most of the abortions in mares in Poland from 1999 to 2012 were associated with non-neuropathogenic strains of EHV-1. However, the presented data indicate that the neuropathogenic genotype of the virus is also present in Polish stud farms. Such a presence suggests that the future emergence of EHM in Poland is probable.

208 Sule, Waidi Folorunso, et.al. (2015). High Seroprevelance of West Nile Virus Antibodies Observed in Horses from Southwestern Nigeria. Vector-Borne and Zoonotic Dis, 15: 218-221 Abstract To investigate exposure of Nigerian horses to West Nile virus (WNV), we determined the seroprevalence rate of anti-WNV antibody in a cohort of 145 horses. Serum samples were collected from three locations in southwestern Nigeria between October, 2011, and July, 2012. The horses were asymptomatic and unvaccinated against WNV at the time of sampling. All sera were tested using a competition enzyme-linked immmunosorbent assay (ELISA) and by an immunoglobulin M (IgM)-specific ELISA. High rates of anti-WNV antibody prevalence were observed in all locations with a mean level of 90.3% (95% confidence interval 84.3– 94.6%). None of the horses had detectable anti-WNV IgM. This is the first ELISA-based report of WNV seroprevalence in Nigerian horses and suggests that WNV is enzootic in the study areas, indicating a potential risk of infection in humans and animals. 209 Taktaz Hafshejani T, et.al. (2015) Molecular Detection of Equine Herpesvirus Types 1 and 4 Infection in Healthy Horses in Isfahan Central and Shahrekord Southwest Regions, Iran. Biomed Res Int.;2015:917854. Abstract This study was undertaken to investigate molecularly the occurrence of EHV-1 and EHV-4 infection among equine population in regions, Iran. Blood samples from 53 and 37 randomly selected horses settled in Isfahan and Shahrekord, Iran, respectively, were collected. Detection of EHV-1 and EHV-4 genes in the blood samples was done using polymerase chain reaction (PCR). Out of 53 and 37 samples fromIsfahan and Shahrekord, 4 (18.18%) and 3 (8.10%) were positive for PCR of EHV-1, respectively. Nine (16.98%) and 6 (16.21%) were positive for PCR of EHV-4, while 6 (11.32%) and 3 (8.10%) were positive for PCR of both EHV-1 and EHV- 4, in Isfahan and Shahrekord, respectively. Of the 7 blood samples positive for EHV-1, 4 (16.66%) and 3 (8.10%) were from horses >3 years old while 2 (18.18%) and 1 (16.66%) were from 2-3 years old horses, in Isfahan and Shahrekord, respectively. Out of the 7 and 3 samples positive for PCR of EHV-1 in Isfahan and Shahrekord, 4 (22.2%) and 1 (7.69%) were Standardbred, while 3 (14.28%) and 2 (13.33%) were Thoroughbreds, respectively. EHV-4 was detected in blood of 4 (22.22%) and 2 (15.83%) Standardbreds and from 4 (19.04%) and 4 (26.66%) Thoroughbred horses in Isfahan and Shahrekord, respectively.This study has shown that horses settled in Isfahan central and Shahrekord southwest regions, Iran, are infected by EHV-1 and EHV-4 and thus serve as potential reservoirs and disseminators of the viruses.

210 Tennent-Brown, BS, Morrice AV. (2015) Reed S. The Equine Neonatal Central Nervous System: Development and Diseases. Vet Clin North Am Equine Pract.;31(3):587-600. Abstract Neonatal encephalopathy (neonatal maladjustment syndrome, hypoxic-ischemic encephalopathy) is the most common neurologic condition affecting newborn foals and shares similarities with perinatal asphyxia syndrome of human infants. In many cases of neonatal encephalopathy there is no obvious episode of acute or chronic hypoxia and other mechanisms likely play a role in the pathogenesis. The role of neurosteroids in neonatal encephalopathy has been investigated and increased concentrations of neuroactive progestagens are found in affected foals; whether these molecules are protective, as has been suggested, or play a role in the pathogenesis is unknown.Neurologic diseases other than neonatal encephalopathy affect foals occasionally and should be considered when evaluating sick foals with clinical signs of neurologic dysfunction.

211 Tirosh-Levy S,et.al. (2015) Prevalence and risk factors for colonization with methicillin resistant Staphylococcus aureus and other Staphylococci species in hospitalized and farm horses in Israel. Prev Vet Med;122(1-2):135-44. Abstract Methicillin-resistant staphylococci (MRS), and specifically Methicillin-resistant Staphylococcus aureus(MRSA) colonization or infection have become a serious emerging condition in equine hospitals, withcomplex concerns regarding animals, personnel and public health. The objectives of this study were toevaluate the prevalence and risk factors for colonization by Staphylococci, MRS, and MRSA among horsesin Israel. Nasal swabs were collected from horses at 17 riding stables (n = 206), and from hospitalizedhorses admitted to a veterinary hospital (n = 84). Species identification was performed by pta gene PCR,RFLP analysis and sequencing. MRS was identified by the presence of mecA. Genetic relatedness of MRSAisolates was determined by spa typing and MLST. SCCmec-type and pvl gene were determined. Uni-variable and multivariable statistical analysis were used to identify potential risk factors. Colonizationwith Staphylococci was found among 3.8% of farm horses and 50.6% of hospitalized horses (p < 0.05). MRSisolates were not found in any of the farm horses, but were isolated from 21.6% of the horses at the veteri-nary hospital, comprising 42.8% of all hospital isolates. MRSA was found exclusively among hospitalizedhorses (7.2%). All MRSA isolates belonged to a unique single multi-drug-resistant clone, ST5-SCCmec V,pvl-negative, spa-type t535. Risk factors for colonization with MRS were pure bred, hospitalization andantibiotic use. This is the first surveillance study of Staphylococci in horses in Israel, and the first reporton the presence of a unique MRSA strain among hospital horses, recognizing the veterinary hospital as apotential reservoir for MRSA, an antibiotic resistant pathogen with human relevance.

212 Tomlinson JE, Reef VB, Boston RC, Johnson AL. (2015) The Association of Fibrinous Pleural Effusion with Survival and Complications in Horses with Pleuropneumonia (2002-2012): 74 Cases. J. Vet Intern Med.;29(5): 1410-7. Abstract Background: Fibrinous parapneumonic pleural effusions are associated with decreased efficacy of pleural fluid drainage and increased risk of medical treatment failure in people, but similar associations have not been established in horses. Hypothesis/Objectives: We hypothesized that fibrin deposition in the pleural cavity of horses with parapneumonic effusions increases the risk of poor outcome. Animals: Seventy four horses with bacterial pleuropneumonia diagnosed by culture and cytology of tracheal aspirates, pleural fluid, or both, and pleural effusion diagnosed by ultrasonographic examination. Methods: Retrospective study of cases was from 2002 to 2012. Information obtained from the medical records included signalment, history, sonographic findings, treatments, and outcome. The primary outcome investigated was survival and secondary outcomes were development of complications and surgical intervention. Fisher’s exact test and logistic regression were applied for categorical variables. A t-test was used to find differences in continuous variables between groups. Results: Seventy four horses met study criteria and 50 (68%) survived. Fibrinous pleural effusion was associated with higher respiratory rate and pleural fluid height at admission, necrotizing pneumonia, increased number of indwelling thoracic drains required for treatment, and decreased survival. Conclusions and clinical importance: Fibrin accumulation in parapneumonic effusions is associated with increased mortality. Direct fibrinolytic treatment might be indicated in affected horses.

213 Tomlinson JE,et.al. (2015) The Use of Recombinant Tissue Plasminogen Activator (rTPA) in The Treatment of Fibrinous Pleuropneumonia in Horses: 25 Cases (2007-2012). J. Vet Intern Med.; 29(5):1403-9. Abstract Background: Information about treatment protocols, adverse effects and outcomes with intrapleural recombinant tissue plasminogen activator (rTPA) use in horses with fibrinous pleuropneumonia is limited. Hypothesis/ Objectives: Describe factors that contribute to clinical response and survival of horses treated with rTPA intrapleurally. Animals: Horses with bacterial pneumonia and fibrinous pleural effusion diagnosed by ultrasonography, that were treated with rTPA intrapleurally. Methods: Retrospective multicenter case series from 2007–2012. Signalment, history, clinical and laboratory evaluation, treatment, and outcome obtained from medical records. Regression analysis used to identify associations between treatments and outcomes. Results: Thirty three hemithoraces were treated in 25 horses, with 55 separate treatments. Recombinant tissue plasminogen activator (375–20,000 lg/hemithorax) was administered 1–4 times. Sonographically visible reduction in fibrin mat thickness, loculations, fluid depth, or some combination of these was seen in 32/49 (65%) treatments. Response to at least 1 treatment was seen in 17/20 (85%) horses with sonographic follow-up evaluation after every treatment. Earlier onset of rTPA treatment associated with increased survival odds. No association was found between cumulative rTPA dose or number of rTPA doses and survival, development of complications, duration of hospitalization or total charges. Clinical evidence of hypocoagulability or bleeding was not observed. Eighteen horses (72%) survived to discharge. Conclusions and clinical importance: Treatment with rTPA appeared safe and resulted in variable changes in fibrin quantity and organization within the pleural space. Recombinant tissue plasminogen activator could be a useful adjunct to standard treatment of fibrinous pleuropneumonia, but optimal case selection and dosing regimen remain to be elucidated

214 Toplu, N., et.al. (2015) West Nile Virus Infection in Horses: Detection by Immunohistochemistry, In Situ Hybridization, and ELISA. Vet Pathol. ;52(6):1073-6. Abstract This study describes the clinicopathologic findings in naturally occurring West Nile virus (WNV) infection in horses. WNV was diagnosed in a foal by immunohistochemical and in situ hybridization methods, and the presence of WNV antibodies was detected in 5 other horses with clinical signs suggestive of WNV infection. At necropsy of the foal, lymph nodes were edematous and enlarged, and the intestines showed diffuse congestion and focal hemorrhages. The most significant histologic lesions in this case were nonsuppurative meningoencephalomyelitis, particularly in the brainstem and spinal cord. Identification of viral RNA by in situ hybridization and viral antigen by immunohistochemistry was concentrated prim‘arily in nerve fibers, glial cells, and their processes in brainstem and spinal cord and, to a lesser extent, within the cerebral hemispheres and cerebellum

215 Velineni S, DeNegri R, Artiushin SC, Timoney JF. (2015) Comparison of specificities of serum antibody responses of horses to clinical infections caused by Streptococcus equi or zooepidemicus. Vet Microbiol.;180(3-4):253-9. Abstract Problem addressed: Streptococcus zooepidemicus (Sz) and its clonal derivative Streptococcus equi (Se) share greater than 96% DNA identity and elicit immune responses to many shared proteins. Identification of proteins uniquely targeted by the immune response to each infection would have diagnostic value. Objective: The aim of the study was to compare serum antibody responses of horses infected by Se or Sz. Methods and approach: Antibody levels were measured to panels of recombinant proteins of Sz and Se in sera of horses and ponies before and after experimental and naturally occurring invasive infections by these organisms. Antibody responses to an Se extract vaccine were also measured. Sera diluted 1:200 were assayed in triplicate using optimum concentrations of 9 and 14 immunoreactive proteins of Se and Sz, respectively. Bound IgG was detected using HRP-Protein G conjugate. Results: Antibodies specific for SeM-N2, IdeE2, Se42.0 and Se75.3 (SEQ2190) were elicited by Se but not by Sz infection. Commercial Se extract vaccine did not elicit responses to IdeE2 or Se75.3. Sz infections resulted in significant (p < 0.01) responses to Sz115, SzM, ScpC, SzP, MAP and streptokinase an indication these proteins are expressed during opportunistic invasions of the respiratory tract. FSR and HylC specific responses were unique to infections by Sz. Conclusions: The data indicate antibodies to IdeE2, Se75.3 and SeM-N2 may be used to distinguish infection by Se from that caused by the closely related Sz. Se infection, but not vaccination with Se extract elicits antibody to IdeE2 and Se75.3.

216 Vieira RF, et.al. (2015) Molecular investigation of hemotropic Mycoplasmas in human beings, dogs and horses in a rural settlement in Southern Brazil. Rev Inst Med Trop Sao Paulo.;57(4):353-7. Abstract The aims of this study were to determine the prevalence of hemoplasmas in a rural Brazilian settlement’s population of human beings, their dogs and horses, highly exposed to tick bites; to identify the tick species parasitizing dogs and horses, and analyze factors associated with their infection. Blood samples from 132 dogs, 16 horses and 100 humans were screened using a pan-hemoplasma SYBR green real-time PCR assay followed by a species-specific TaqMan real-time PCR. A total of 59/132 (44.7%) dog samples were positive for hemoplasmas (21 Mycoplasma haemocanis alone, 12 ‘Candidatus Mycoplasma haematoparvum’ alone and 21 both). Only 1/100 (1.0%) human sample was positive by qPCR SYBR green, with no successful amplification of 16S rRNA or 23 rRNA genes despite multiple attempts. All horse samples were negative. Dogs >1 year of age were more likely to be positive for hemoplasmas (p = 0.0014). In conclusion, although canine hemoplasma infection was highly prevalent, cross-species hemoplasma transmission was not observed, and therefore may not frequently occur despite overexposure of agents and vectors.

217 Wagner B, et.al. (2015) Antibody and cellular immune responses of naïve mares to repeated vaccination with an inactivated equine herpesvirus vaccine. Vaccine. ;33(42):5588-97. Abstract Equine herpesvirus type 1 (EHV-1) continues to cause severe outbreaks of abortions or myeloen-cephalopathy in horses despite widely used vaccination. The aim of this work was to determine theeffects of frequent vaccination with an inactivated EHV vaccine on immune development in horses. Fif-teen EHV-1 naïve mares were vaccinated a total of 5 times over a period of 8 months with intervals of 20,60, 90 and 60 days between vaccine administrations. Total antibody and antibody isotype responses wereevaluated with a new sensitive EHV-1 Multiplex assay to glycoprotein C (gC) and gD for up to 14 monthsafter initial vaccination. Antibodies peaked after the first two vaccine doses and then declined despite athird administration of the vaccine. The fourth vaccine dose was given at 6 months and the gC and gD anti-body titers increased again. Mixed responses with increasing gC but decreasing gD antibody values wereobserved after the fifth vaccination at 8 months. IgG4/7 isotype responses mimicked the total Ig antibodyproduction to vaccination most closely. Vaccination also induced short-lasting IgG1 antibodies to gC, butnot to gD. EHV-1-specific cellular immunity induced by vaccination developed slower than antibodies,was dominated by IFN- _ producing T-helper 1 (Th1) cells, and was significantly increased compared topre-vaccination values after administration of 3 vaccine doses. Decreased IFN- _ production and reducedTh1-cell induction were also observed after the second and fourth vaccination. Overall, repeated EHVvaccine administration did not always result in increasing immunity. The adverse effects on antibodyand cellular immunity that were observed here when the EHV vaccine was given in short intervals mightin part explain why EHV-1 outbreaks are observed worldwide despite widely used vaccination. The find-ings warrant further evaluation of immune responses to EHV vaccines to optimize vaccination protocolsfor different vaccines and horse groups at risk.

218 Wang, G. (2015) Effects of weather and landscape on the equine West Nile virus infection risk in Mississippi, USA. Geospat Health;10(2):357. Abstract The West Nile virus (WNv) continues to be a public health concern in North America. Dry weather appears to increase human WNv infection risks, but it is uncertain whether dry weather conditions exert similar effects on the corresponding equine WNv infection. This study assessed the effects of precipitation of the previous year and land cover diversity on the equine WNv risk of Mississippi, USA, at the county level in the year 2002 using Bayesian hierarchical models. The risk estimated for 2002 was found to be inversely related to annual precipitation of the preceding year. Equine WNv risks were lower with greater land cover diversity probably due to the diluting effects of biodiversity. Correlation between the equine and human WNv risks was positive but relatively low. Dry weather conditions of the previous year might reduce mosquito competitors and predators and subsequently increase mosquito abundances and equine WNv risks in agricultural areas with low biodiversity.

219 Whitfield-Cargile, Canaan M., et.al. (2015) Composition and Diversity of the Fecal Microbiome and Inferred Fecal Metagenome Does Not Predict Subsequent Pneumonia Caused by Rhodococcus equi in Foals. PLoS ONE 10(8): e0136586 Abstract In equids, susceptibility to disease caused by Rhodococcus equi occurs almost exclusively in foals. This distribution might be attributable to the age-dependent maturation of immunity following birth undergone by mammalian neonates that renders them especially susceptible to infectious diseases. Expansion and diversification of the neonatal microbiome contribute to development of immunity in the gut. Moreover, diminished diversity of the gastrointestinal microbiome has been associated with risk of infections and immune dysregulation. We thus hypothesized that varying composition or reduced diversity of the intestinal microbiome of neonatal foals would contribute to increased susceptibility of their developing R. equi pneumonia. The composition and diversity indices of the fecal microbiota at 3 and 5 weeks of age were compared among 3 groups of foals: 1) foals that subsequently developed R. Equi pneumonia after sampling; 2) foals that subsequently developed ultrasonographic evidence of pulmonary abscess formation or consolidation but not clinical signs (subclinical group); and, 3) foals that developed neither clinical signs nor ultrasonographic evidence of pulmonary abscess formation or consolidation. No significant differences were found among groups at either sampling time, indicating absence of evidence of an influence of composition or diversity of the fecal microbiome, or predicted fecal metagenome, on susceptibility to subsequent R. equi pneumonia. A marked and significant difference identified between a relatively short interval of time appeared to reflect ongoing adaptation to transition from a milk diet to a diet including available forage (including hay) and access to concentrate fed to the mare. 220 Wobeser BK. (2015) Skin Diseases in Horses. Vet Clin North Am Equine Pract.;31(2):359-76. Abstract Skin disease in horses is a common and potentially challenging clinical problem. Information pertaining to skin disease is lacking in horses when compared with that in other companion animal species. Certainly, both horse- specific and location-specific patterns are present, but these can often be confounded by other factors. There are many possible ways in which to organize skin disease; in this article, they are organized based loosely on their most common clinical feature (Table 1). Space limits the number of conditions that can be described here, and those chosen were seen relatively frequently in a multiinstitutional study of equine biopsies

221 Yildirim, Y, Yilmaz V, Kirmizigul AH. (2015) Equine herpes virus type 1 (EHV-1) and 4 (EHV-4) infections in horses and donkeys in northeastern Turkey. Iran J Vet Res. ;16(4):341-4. Abstract The herpesviruses infections in equides are caused by five different serotypes of viruses, belonging to family Herpesviridae. The goal of this study was to conduct a seroepidemiological investigation of equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) in horses and donkeys raised in two provinces and their villages in northeastern Turkey. A total of 666 samples from 423 horses and 243 donkeys that were not immunized against these infections were tested with ELISA. While 52.48% of tested horse sera was found to carry specific antibodies to EHV-1, 83.69% of these serums were found to carry specific antibodies to EHV-4. 51. Eighty- five percent of analyzed donkey samples tested positive for EHV-1 and 64.20% of these samples tested positive for EHV-4 antibodies. When the horse and donkey samples were evaluated together, 52.25% were seropositive for EHV-1 and 76.58% were seropositive for EHV-4. This study showed that EHV-1 and EHV-4 infections are quite common in the horses and donkeys being raised in the areas where the study was carried out. In addition, since the area where the study was carried out in the borders of Armenia and Georgia, the high level of seropositive results for these infections leads to the conclusion that we should consider the risk of diseases spreading to neighboring countries. This is the first study to serologically identify EHV-1 and EHV-4 infections in donkeys raised in Turkey. 222 Abutarbush SM, Al-Majali AM. West Nile virus infection in horses in Jordan: clinical cases, seroprevalence and risk factors. Transbound Emerg Dis. 2014;61 Spl 1:1-6. Abstract The objectives of this study are to report clinical WNV infection in horses and to determine the seroprevalence of and risk factors for WNV infection in horses in Jordan. In late summer and early fall of 2012, two mares were presented for evaluation of neurological signs. The first mare had hind-limb ataxia. The second mare was slightly depressed and lethargic. She had ataxia in her four limbs and cranial nerves deficits. Both horses were found positive for WNV IgM antibodies using commercial IgM-capture ELISA test. Both horses were treated symptomatically and recovered uneventfully. The occurrence of clinical cases initiated the need for a seroprevalence and risk factors study. Two hundred and fifty-three normal horses were randomly enrolled in the study. Enrolled horses were grouped into five major regions according to the geographical proximity and climatic similarities. From each region, around 50 horses were sampled. The serum collected from each horse was screened by a competitive ELISA, and those that reacted positive using the previous ELISA test were further tested using commercial IgM-capture ELISA test. Sixty- three horses (24.9%) of the 253 surveyed were seropositive to WNV. Of the 63 horses, none had IgM antibodies for WNV. The region with the highest prevalence was Jordan Valley and Balqa. Horses used for polo (OR = 9.77; 95%CI = 1.32–25.44) and horses located in Jordan Valley and Balqa region (OR = 13.31; 95% CI = 2.33–32.54) were identified as risk factors for seropositivity to WNV in Jordan. These risk factors were attributed to the hot and humid weather, which enhance vector availability. West Nile virus appears to be endemic in Jordan. Future studies are warranted to evaluate the virus situation in the country during the next few years in an attempt to control it. 223 Aharonson-Raz, K, et.al. (2014) Spatial and temporal distribution of West Nile virus in horses in Israel (1997-2013)--from endemic to epidemics. PLoS One;9(11):e113149. Abstract With the rapid global spread of West Nile virus (WNV) and the endemic state it has acquired in new geographical areas, we hereby bring a thorough serological investigation of WNV in horses in a longstanding endemic region, such as Israel. This study evaluates the environmental and demographic risk factors for WNV infection in horses and suggests possible factors associated with the transition from endemic to epidemic state. West Nile virus seroprevalence in horses in Israel was determined throughout a period of more than a decade, before (1997) and after (2002 and 2013) the massive West Nile fever outbreak in humans and horses in 2000. An increase in seroprevalence was observed, from 39% (113/290) in 1997 to 66.1% (547/827) in 2002 and 85.5% (153/179) in 2013, with persistent significantly higher seroprevalence in horses situated along the Great Rift Valley (GRV) area, the major birds’ migration route in Israel. Demographic risk factors included age and breed of the horse. Significantly lower spring precipitation was observed during years with increased human incidence rate that occurred between 1997–2007. Hence, we suggest referring to Israel as two WNV distinct epidemiological regions; an endemic region along the birds’ migration route (GRV) and the rest of the country which perhaps suffers from cyclic epidemics. In addition, weather conditions, such as periods of spring drought, might be associated with the transition from endemic state to epidemic state of WNV 224 Bowen RA, et.al. Protection of horses from West Nile virus Lineage 2 challenge following immunization with a whole, inactivated WNV lineage 1 vaccine. Vaccine. 2014;32(42):5455-5459 Abstract Over the last years West Nile virus (WNV) lineage 2 has spread from the African to the European conti-nent. This study was conducted to demonstrate efficacy of an inactivated, lineage 1-based, WNV vaccine (Equip ®WNV) against intrathecal challenge of horses with a recent isolate of lineage 2 WNV. Twentyhorses, sero- negative for WNV, were enrolled and were randomly allocated to one of two treatmentgroups: an unvaccinated control group (T01, n = 10) and a group administered with Equip®WNV (T02,n = 10). Horses were vaccinated at Day 0 and 21 and were challenged at day 42 with WNV lineage 2, NeaSanta/Greece/2010. Personnel performing clinical observations were blinded to treatment allocation.Sixty percent of the controls had to be euthanized after challenge compared to none of the vaccinates. Asignificantly lower percentage of the vaccinated animals showed clinical disease (two different clinicalobservations present on the same day) on six different days of study and the percentage of days with clin-ical disease was significantly lower in the vaccinated group. A total of 80% of the non-vaccinated horsesshowed viremia while only one vaccinated animal was positive by virus isolation on a single occasion.Vaccinated animals started to develop antibodies against WNV lineage 2 from day 14 (2 weeks after thefirst vaccination) and at day 42 (the time of onset of immunity) they had all developed a strong antibodyresponse. Histopathology scores for all unvaccinated animals ranged from mild to very severe in eachof the tissues examined (cervical spinal cord, medulla and pons), whereas in vaccinated horses 8 of 10animals had no lesions and 2 had minimal lesions in one tissue. In conclusion, Equip®WNV significantlyreduced the number of viremic horses, the duration and severity of clinical signs of disease and mortalityfollowing challenge with lineage 2 WNV. 225 Dongga, Rambu Eryani Diki (2014) Adopsi Teknologi Pengendalian Penyakit Surra Oleh Peternak Kuda Di Kabupaten Sumba Timur, Nusa Tenggara Timur.- Buletin Veteriner Udayana, 6 49-57. Abstract Peternakan merupakan sektor penting dalam menunjang perekonomian di Kabupaten Sumba Timur. Tetapi, adanya penyakit surra merupakan masalah yang akan mengancam populasi kuda. Berbagai upaya telah dilakukan oleh pemerintah yaitu dengan melakukan penyuluhan, pengaturan, dan pelayanan. Namun, keberadaan penyakit surra masih belum dapat teratasi dengan baik. Tujuan penelitian ini adalah untuk 1) mengetahui tingkat perilaku (pengetahuan, keterampilan, dan sikap) peternak tentang pengendalian penyakit surra; 2) mengetahui tingkat adopsi tekonologi pengendalian penyakit surra; 3) menganalisis hubungan penyuluhan tentang pengendalian penyakit surra terhadap perubahan perilaku (pengetahuan, keterampilan, dan sikap peternak; 4) menganalisis hubungan antara perilaku peternak dengan tingkat adopsi teknologi pengendalian penyakit surra. Penentuan responden dalam penelitian ini dilakukan secara stratified random sampling dari seluruh peternak di daerah penelitian yang terkena penyakit surra di Kabupaten Sumba Timur. Responden peternak yang dipakai dalam penelitian ini ditentukan secara proporsional yaitu diambil 10% dari setiap kecamatan di mana penyakit surra lebih banyak terjangkit. Jumlah sampel ditentukan berdasarkan rumus populasi Slovin (Consuelo, 1993). Hasil penelitian menunjukkan bahwa 1) pengetahuan dan keterampilan peternak kuda di Kabupaten Sumba Timur mengenai teknologi pengendalian penyakit surra termasuk dalam kategori sedang, sedangkan sikap peternak kuda termasuk dalam kategori positif; 2) tingkat adopsi teknologi pengendalian penyakit surra oleh peternak kuda termasuk dalam kategori sedang; 3) penyuluhan tentang pengendalian penyakit surra berhubungan positif dengan tingkat pengetahuan peternak, tetapi tidak dengan keterampilan dan sikap peternak; 4) sikap peternak memiliki hubungan yang nyata dengan tingkat adopsi teknologi pengendalian penyakit surra di Kabupaten Sumba Timur, tetapi tidak dengan pengetahuan dan keterampilan peternak

226 van den Hurk, Andrew F., et.al. (2014) Role of enhanced vector transmission of a new West Nile virus strain in an outbreak of equine disease in Australia in 2011. Parasites & Vectors 2014, 7:586 Abstract Background: In 2011, a variant of West Nile virus Kunjin strain (WNVKUN) caused an unprecedented epidemic of neurological disease in horses in southeast Australia, resulting in almost 1,000 cases and a 9% fatality rate. We investigated whether increased fitness of the virus in the primary vector, Culex annulirostris, and another potential vector, Culex australicus, contributed to the widespread nature of the outbreak. Methods: Mosquitoes were exposed to infectious blood meals containing either the virus strain responsible for the outbreak, designated WNVKUN2011, or WNVKUN2009, a strain of low virulence that is typical of historical strains of this virus. WNVKUN infection in mosquito samples was detected using a fixed cell culture enzyme immunoassay and a WNVKUN- specific monoclonal antibody. Probit analysis was used to determine mosquito susceptibility to infection. Infection, dissemination and transmission rates for selected days post- exposure were compared using Fisher?s exact test. Virus titers in bodies and saliva expectorates were compared using t-tests. Results: There were few significant differences between the two virus strains in the susceptibility of Cx. Annulirostris to infection, the kinetics of virus replication and the ability of this mosquito species to transmit either strain. Both strains were transmitted by Cx. annulirostris for the first time on day 5 post- exposure. The highest transmission rates (proportion of mosquitoes with virus detected in saliva) observed were 68% for WNVKUN2011 on day 12 and 72% for WNVKUN2009 on day 14. On days 12 and 14 post-exposure, significantly more WNVKUN2011 than WNVKUN2009 was expectorated by infected mosquitoes. Infection, dissemination and transmission rates of the two strains were not significantly different in Culex australicus. However, transmission rates and the amount of virus expectorated were significantly lower in Cx. australicus than Cx. annulirostris. Conclusions: The higher amount of WNVKUN2011 expectorated by infected mosquitoes may be an indication that this virus strain is transmitted more efficiently by Cx. annulirostris compared to other WNVKUN strains. Combined with other factors, such as a convergence of abundant mosquito and wading bird populations, and mammalian and avian feeding behaviour by Cx. annulirostris, this may have contributed to the scale of the 2011 equine epidemic 227 Metz, G.E., et.al. ( 2014) The equine arteritis virus isolate from the 2010 Argentinian outbreak. Rev. sci. tech. Off. int. Epiz., 33: 937- Abstract A semen sample from a stallion infected during the 2010 equine arteritis virus (EAV) outbreak was received for viral isolation prior to castration of the animal. The virus was identified using a polyclonal antibody immunofluorescence test. Reverse-transcription polymerase chain reaction (RT-PCR) was used to amplify a region of the GP5 gene with primers GL105F and GL673R. The PCR products were purified and sequences of both strands were determined in a MegaBACETM 1000 with inner primers CR2 and EAV32. A phylogenetic dataset was built with the previously reported sequences of five strains isolated in Argentina, together with a group of selected sequences obtained from GenBank. The unrooted neighbour-joining tree was constructed using molecular evolutionary genetic analysis (MEGA) and bootstrap analyses were conducted using 1,000 replicate datasets. Evolutionary distances were computed using the maximumcomposite likelihood method. A NetNGlyc server analysis at the Technical University of Denmark (www.cbs.dtu.dk/services/NetNGlyc/) was used to predict Nglycosylation in GP5 sequences. The phylogenetic analysis revealed that the new strain (GLD- LP-ARG), together with other strains previously isolated, belongs to the European group EU-1 but in a different branch. The new strain shows 99% nucleotide identity with strain A1 and 98.1% with the Belgian strain 08P178. Persistently infected stallions and their cryopreserved semen constitute a reservoir of EAV, which ensures its persistence in the horse population around the world. These findings reinforce the importance of careful monitoring of persistently infected stallions, as well as semen straws, by RT-PCR or test mating, in accordance with national regulations 228 Mughini-Gras, L, et.al. (2014) Ecological niche modelling of potential West Nile virus vector mosquito species and their geographical association with equine epizootics in Italy. Ecohealth.;11:120-32. Abstract In Italy, West Nile virus (WNV) equine outbreaks have occurred annually since 2008. Characterizing WNV vector habitat requirements allows for the identification of areas at risk of viral amplification and transmission. Maxent-based ecological niche models were developed using literature records of 13 potential WNV Italian vector mosquito species to predict their habitat suitability range and to investigate possible geographical associations with WNV equine outbreak occurrence in Italy from 2008 to 2010. The contribution of different environmental variables to the niche models was also assessed. Suitable habitats for Culex pipiens, Aedes albopictus, and Anopheles maculipennis were widely distributed; Culex modestus, Ochlerotatus geniculatus, Ochlerotatus caspius, Coquillettidia richiardii, Aedes vexans, and Anopheles plumbeus were concentrated in north-central Italy; Aedes cinereus, Culex theileri, Ochlerotatus dorsalis, and Culiseta longiareolata were restricted to coastal/southern areas. Elevation, temperature, and precipitation variables showed the highest predictive power. Host population and landscape variables provided minor contributions. WNV equine outbreaks had a significantly higher probability to occur in habitats suitable for Cx. modestus and Cx. pipiens, providing circumstantial evidence that the potential distribution of these two species coincides geographically with the observed distribution of the disease in equines. 229 Williams, JH., et.al. (2014) Pathology of fatal lineage 1 and 2 West Nile virus infections in horses in South Africa. J. S. Afr Vet Assoc.;85(1):1105 Abstract Since 2007, West Nile virus (WNV) has been reported in South African horses, causing severe neurological signs. All cases were of lineage 2, except for one case that clustered with lineage 1 viruses. In the present study, gross and microscopic lesions of six South African lineage 2-infected horses and the one lineage 1 case are described. Diagnoses were confirmed by real-time reverse-transcriptase polymerase chain reaction (RT-PCR) of central nervous system (CNS) tissue and one by RT-PCR of a brain virus isolate. The CNS of all cases was negative by RT-PCR or immunohistochemistry (IHC) for African horse sickness (AHS), equine encephalosis virus, equine herpes viruses 1 and 4, other zoonotic flaviviruses, alphaviruses, and shunivirus, and either by immunofluorescence or IHC for rabies. Gross visceral lesions were nonspecific but often mimicked those of AHS. The CNS histopathology of WNV lineage 2 cases resembled the nonsuppurative polioencephalomyelitis reported in the Northern Hemisphere lineage 1 and recent Hungarian lineage 2 cases. Occasional meningitis, focal spinal ventral horn poliomalacia, dorsal and lateral horn poliomyelitis, leucomyelitis, asymmetrical ventral motor spinal neuritis and frequent olfactory region involvement were also seen. Lineage 2 cases displayed marked variations in CNS lesion severity, type and distribution, and suggested various viral entry routes into the CNS, based on findings in experimental mice and hamsters. Lineage 1 lesions were comparable to the milder lineage 2 cases. West Nile virus IHC on CNS sections with marked lesions from all cases elicited only two antigen-positive cells in the olfactory cortex of one case. The presence in the CNS of T-lymphocytes, B-lymphocytes, plasma cells and macrophage-monocytes was confirmed by cluster of differentiation (CD) 3, CD20, multiple myeloma oncogene 1 (MUM1) and macrophage (MAC) 387 IHC. 230 Berxholi K, et.al. (2013) Indigenous West Nile virus infections in horses in Albania. Transbound Emerg Dis.;60 Supl 2:45-50 Abstract Serum samples collected from 167 equines of 12 districts in Albania were tested for West Nile virus–specific antibodies by enzyme-linked immunosorbent assay and virus neutralization assay, using WNV lineage 1 and 2. In addition, 95 bird serum samples from Albania and 29 horse samples from Kosovo were tested in ELISA. An overall seroprevalence rate of 22% was found in horses from Albania, whereas no specific antibodies were found in the equine samples from Kosovo and the bird samples. This is the first report indicating WNV infections in animals in Albania, and the first reported seroprevalence study conducted for Kosovo. These results provide evidence for widespread infections of WNV in Albania. 231 Burgueño A,et.al. (2013) Seroprevalence of St. Louis encephalitis virus and West Nile virus (Flavivirus, Flaviviridae) in horses, Uruguay. Biomed Res Int.;2013:582957. Abstract St. Louis encephalitis virus (SLEV) andWest Nile virus (WNV) belong to the Japanese encephalitis antigenic complex (Flavivirus genus, Flaviviridae family). They show antigenic close relationships and share many similarities in their ecology. Both are responsible for serious human diseases. The aim of this study was to investigate the presence of neutralizing antibodies to these viruses in horses from Uruguay. To do this, 425 horse sera were collected in 2007 and analyzed by plaque reduction neutralization tests. As a result, 205 sera (48.2%) were found positive for SLEV, with titers ranging between 10 and 80. Two sera remained inconclusive, since they showed low titers to WNV and SLEV (10 and 20), not allowing us to demonstrate activity of WNV in our territory.This is the first report of circulation of SLEV in horses in Uruguay 232 Lan, DL, Wang CS, et.al. (2013) Serological investigations on West Nile virus in birds and horses in Shanghai, China. Epidemiol Infect.;141(3):596-600. Abstract West Nile virus (WNV) infection is an emerging zoonosis that threatens global public health. In this study, a total of 95 bird serum samples from 14 species and 341 horse serum samples were collected from 2008 to 2010 in Shanghai, China. All serum samples were screened initially for WNV-reactive antibodies using a competitive ELISA. The positive samples detected by ELISA were further confirmed using a plaque-reduction neutralization test (PRNT) for WNV and its most closely related flaviviruses in the area to avoid false positives due to cross-reactivity. Five (5.3%) of the bird serum samples and none (0.0%) of the horse serum samples tested positive for WNV antibodies. The findings strongly suggest that some of the birds, specifically the resident birds in China, had been exposed to WNV. 233 Mann, RA,et.al. (2013) Molecular characterization and phylogenetic analysis of Murray Valley encephalitis virus and West Nile virus (Kunjin subtype) from an arbovirus disease outbreak in horses in Victoria, Australia, in 2011. J Vet Diagn Invest.;25: 35-44. Abstract Virus was detected in the central nervous system (CNS) tissue of 11 horses from Victoria that died displaying neurological symptoms during an outbreak of disease in Australia in 2011. Five horses were identified as being infected with Murray Valley encephalitis virus (MVEV) and 6 as being infected with West Nile virus subtype Kunjin (WNVKUN). Analysis of partial sequence information from the NS5 and E genes indicated that the MVEVs within the samples were highly homogenous and all belonged to lineage I, which is enzootic to the tropical regions of northern Australia. Likewise, analysis of partial NS5 and E gene and full genome sequences indicated that the WNVKUN within the samples were also highly homogenous and clustered with WNV lineage 1, clade b, which is consistent with other WNVKUN isolates. Full genomes of 1 MVEV isolate and 2 WNVKUN isolates were sequenced and characterized. The genome sequences of Victorian WNVKUN are almost identical (3 amino acid differences) to that of the recently sequenced WNV isolate WNVNSW2011. Metagenome sequencing directly from CNS tissue identified the presence of WNVKUN and MVEV within infected CNS tissue 234 Mulatti P, et.al. (2013) West Nile virus in north-eastern Italy, 2011: entomological and equine IgM- based surveillance to detect active virus circulation. Zoonoses Public Health.;60:375-82. Abstract Since 2008, West Nile Virus (WNV) has expanded its range in several Italian regions, and its yearly recurrence suggests the virus may have become endemic in some areas. In 2011, a new plan based also on the detection of IgM antibodies was implemented in the north-eastern Italian regions of Veneto and Friuli Venezia Giulia, aiming to early detect WNV infections in areas where the virus had already circulated during the previous summers, and in adjacent zones. From July to November 2011, 1880 sera from 521 equine premises were screened by a commercial IgM capture ELISA. Mosquitoes were captured by CDC-CO2 traps at 61 locations in the two regions. Collected mosquitoes were identified, pooled by species/date/location and examined by real-time RT-PCR and sequencing. Passive surveillance was carried out on clinically affected horses and non-migratory wild birds found dead. IgM sero- positive equines were detected in 19 holdings, five in the area with WNV circulation (AWC) and 14 in the surveillance area (SA); 10 more horse premises tested positive to further serological controls within 4 km of the positive holdings. A total of 85 398 mosquitoes of 15 species were collected and 2732 pools examined. Five Culex pipiens pools tested positive for the presence of WNV. Passive surveillance on non-migratory wild birds allowed detection of the virus only in one found dead collared dove (Streptopelia decaocto), of 82 birds sampled. The WNV belonged to the lineage 2, which had been isolated for the first time in Italy earlier in 2011. By the first week of October, nine human cases had been confirmed in the same area. The implementation of a protocol combining IgM screening of horses with surveillance on mosquito vectors proved to be valuable for early detecting WNV circulation. 235 Owen, J. C., et.al. (2013) Leukocyte Response to Eastern Equine Encephalomyelitis Virus in a Wild Passerine Bird.- Avian Diseases, 57:744–749, Abstract Leukocyte counts are frequently used to assess the immunologic status of animals; however, few studies have directly looked at the predictive value of leukocyte counts and an animal’s ability to respond to an infection with a pathogen. Understanding how an animal’s leukocyte profile is altered by an active infection can assist with interpretation of leukocyte profiles in animals for which infection status is not known. In this study we examine the leukocyte counts of gray catbirds (Dumetella carolinensis) infected with eastern equine encephalomyelitis virus (EEEV). Blood smears were collected from infected catbirds on 24, 2, 5, and 14 days postinoculation (dpi) with EEEV, and from a corresponding uninfected control group, to monitor leukocyte counts. Although we found that preinfection leukocyte counts were not a reliable predictive of a catbird’s viremia, we did find that infected catbirds exhibited significant hematologic changes in response to EEEV infection. We observed a significant drop in all subpopulations of leukocytes (i.e., lymphocytes, monocytes, and granulocytes) following infection. Lymphocytes and granulocytes still had not recovered to preinfection levels at 14 dpi. Uninfected catbirds also exhibited statistically significant changes in leukocyte counts, but this was due to a slight increase at 14 dpi and was not considered biologically relevant. Studies such as this can provide important information for field ecoimmunologists that use leukocyte counts to assess immunocompetence in free-living animals.

236 Ozkul A, et.al. (2013) Concurrent occurrence of human and equine West Nile virus infections in Central Anatolia, Turkey: the first evidence for circulation of lineage 1 viruses. Int J Infect Dis. ;17: e546-51. Abstract Background: West Nile fever is an important zoonotic infection caused by West Nile virus (WNV), a member of the Flaviviridae. Previous serological data from Turkey suggest widespread WNV circulation. This report includes cases of human and equine WNV infections occurring concurrently, and manifesting as central nervous system infections, in two neighboring provinces of Central Anatolia, Turkey. A partial phylogenetic analysis of the causative virus is given for the first time. Methods: The cases were reported in February (horses) and March (human). Symptoms of the disease were similar in the two species, characterized by neurological manifestations suggesting meningoencephalitis. Real-time/nested PCRs and commercial immunoassays and a plaque reduction neutralization assay were employed for the detection of viral RNA and specific antibodies, respectively. Results: WNV RNAs were detected in buffy coat (horses) and cerebrospinal fluid (human) samples. Partial nucleotide sequences of the E-gene coding region revealed that the strains are closely related to viruses of lineage 1, clade 1a. Accompanying equine serosurveillance demonstrated WNV-specific antibodies in 31.6% of the samples. Conclusions: This is the first report of acute WNV infections caused by lineage 1 strains from Turkey, in concordance with previous reports from some European and North African countries. 237 Schulman, Martin Lance, et.al. (2013) Contagious equine metritis: Artificial reproduction changes the epidemiologic paradigm. Veterinary Microbiology 167 2–8. Abstract Recent CEM outbreak reports reflect a novel epidemiologic manifestation with a markedly different risk association for transmission via artificial reproduction and subsequent to inadvertent importation of unapparent carrier stallions. Artificial breeding has an increased association with horizontal or fomite-associated transmission. Reported risk factors include inadequate biosecurity protocols at centralised breeding facilities associated with stallion management and methods of semen collection, processing and transport. Detection of carriers is based on traditional bacteriology from genital swabs and despite limitations inherent to Taylorella equigenitalis is currently the gold standard applied in all international trade and movement protocols. These limitations are reported to be overcome by PCR assays improving diagnostic sensitivity and specificity, practicality, turn-around times, through-put and cost efficacy. Molecular methods have increased understanding of the Taylorelleae, facilitate epidemiologic surveillance and outbreak control strategies. Validation and international regulatory acceptance of a robust PCR-based assay and the undefined risks in association with cryopreserved semen and embryos are future areas warranting further investigation. 238 Silva JR, et.al. (2013) Serologic survey of West Nile virus in horses from Central-West, Northeast and Southeast Brazil. Mem Inst Oswaldo Cruz.;108(7):921-3 Abstract Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country 239 Vignjević G,et.al. (2013) Equine seroprevalence rates as an additional indicator for a more accurate risk assessment of the West Nile virus transmission. Coll Antropol.;37(3): 949-56. Abstract The West Nile Virus (WNV) is a zoonotic arbovirus that has recently been causing outbreaks in many countries in southern and Central Europe. In 2012, for the first time, it caused an outbreak in eastern Croatia with total of 7 human clinical cases. With an aim of assisting public health personnel in order to improve survey protocols and vector control, the high risk areas of the WNV transmission were estimated and mapped. The study area included cities of Osijek and Slavonski Brod and 8 municipalities in Vukovarsko-Srijemska County. Risk estimation was based on seroprevalence of WNV infections in horses as an indicator of the virus presence, as well as the presence of possible WNV mosquito vectors with corresponding vector competences. Four mosquito species considered as possible WNV vectors are included in this study: Aedes vexans, Culex modestus, Culex pipiens and Ochlerotatus caspius. Mosquitoes were sampled using dry-ice baited CDC trap, twice a month, between May and October. This study suggests that the two mosquito species present the main risk of WNV transmission in eastern Croatia: the Culex pipiens – because of good vector competence and the Aedes vexans – because of the very high abundances. As a result, these two species should be focus of future mosquito surveillance and a vector control management 240 Walter, Jasmin, et.al. (2013) Clinical observations and management of a severe equine herpesvirus type 1 outbreak with abortion and encephalomyelitis. Acta Veterinaria Scandinavica, 55:19 Abstract

Latent equine herpesvirus type 1 (EHV-1) infection is common in horse populations worldwide and estimated to reach a prevalence nearing 90% in some areas. The virus causes acute outbreaks of disease that are characterized by abortion and sporadic cases of myeloencephalopathy (EHM), both severe threats to equine facilities. Different strains vary in their abortigenic and neuropathogenic potential and the simultaneous occurrence of EHM and abortion is rare. In this report, we present clinical observations collected during an EHV-1 outbreak caused by a socalled “neuropathogenic” EHV-1 G2254/D752 polymerase (Pol) variant, which has become more prevalent in recent years and is less frequently associated with abortions. In this outbreak with 61 clinically affected horses, 6/7 pregnant mares aborted and 8 horses developed EHM. Three abortions occurred after development of EHM symptoms. Virus detection was performed by nested PCR targeting gB from nasal swabs (11 positive), blood serum (6 positive) and peripheral blood mononuclear cells (9 positive) of a total of 42 horses sampled. All 6 fetuses tested positive for EHV-1 by PCR and 4 by virus isolation. Paired serum neutralization test (SNT) on day 12 and 28 after the index case showed a significant (≥ 4-fold) increase in twelve horses (n = 42; 28.6%). This outbreak with abortions and EHM cases on a single equine facility provided a unique opportunity for the documentation of clinical disease progression as well as diagnostic procedures.

241 Ziegler U,et.al. (2013) Use of competition ELISA for monitoring of West Nile virus infections in horses in Germany. Int J Environ Res Public Health.;10: 3112-20. Abstract West Nile virus (WNV) is a mosquito-borne viral pathogen of global importance and is considered to be the most widespread flavivirus in the World. Horses, as dead-end hosts, can be infected by bridge mosquito vectors and undergo either subclinical infections or develop severe neurological diseases. The aim of this study was to detect WNV specific antibodies in horses in Germany as an indicator for an endemic circulation of WNV. Sera from more than 5,000 horses (primarily fallen stock animals) were collected in eight different federal states of Germany from 2010 to 2012. Sera were screened by a competitive ELISA and positive reactions were verified by an indirect IgM ELISA and/or by virus neutralization tests (VNT) for WNV and Tick-borne encephalitis virus (TBEV) in order to exclude cross-reacting antibody reactions. In essence WNV specific antibodies could not be detected in any of the horse sera. Not surprisingly, a small number of sera contained antibodies against TBEV. It is noteworthy that equine sera were often collected from horse carcasses and therefore were of poor quality. Nonetheless, these sera were still suitable for WNV ELISA testing, i.e., they did not produce a high background reaction which is a frequently observed phenomenon. According to these data there is no evidence for indigenous WNV infections in horses in Germany at present 242 Ziegler, U, et.al. (2013) West nile virus antibody prevalence in horses of Ukraine. Viruses.;5(10):2469-82. Abstract West Nile virus (WNV) is a mosquito-borne virus of global importance. Over the last two decades, it has been responsible for significant numbers of cases of illness in humans and animals in many parts of the world. In Ukraine, WNV infections in humans and birds were first reported more than 25 years ago, yet the current epidemiological status is quite unclear. In this study, serum samples from over 300 equines were collected and screened in order to detect current WNV activity in Ukraine with the goal to estimate the risk of infection for humans and horses. Sera were tested by enzyme-linked immunosorbent assay (ELISA) and virus neutralization assay (NT) to detect WNV-specific antibodies. The results clearly revealed that WNV circulates in most of the regions from which samples were obtained, shown by a WNV seroprevalence rate of 13.5% of examined horses. This is the first topical report indicating the presence of WNV infections in horses in Ukraine, and the results of this study provide evidence of a widespread WNV circulation in this country. 243 Zink, SD, et.al. (2013) Quadraplex qRT-PCR assay for the simultaneous detection of Eastern equine encephalitis virus and West Nile virus. Diagn Microbiol Infect Dis.;77:129-32. Abstract In order to increase testing throughput and reduce cost, we developed a multiplex real-time assay that identifies both Eastern equine encephalitis virus and West Nile virus. The assay allows for the screening for the presence of both the nonstructural and envelope genes of both viruses simultaneously allowing for confirmatory testing to be done in a single assay. We utilized newly designed primers and probes, each labeled with a unique fluorescent label allowing for differentiation using an ABI 7500 real-time PCR machine. The use of Quanta Biosciences qScript XLT One-Step RT-qPCR® Toughmix allowed for a quadraplex assay without loss of sensitivity when compared to the previously run singleplex reaction as seen with viral RNA PFU control dilution series. There was no cross reactivity between the viruses within the reaction, and upon utilization of the assay during surveillance, there was no cross reactivity with other historically encountered arthropod-borne viruses. The results from the quantitative Reverse Transcriptase – Polymerase Chain Reaction were comparable to those achieved by cell culture which was performed on a subset of the field mosquito pools screened during the 2012 surveillance season. The multiplex assay resulted in savings in both time and resources for the lab and faster turn-around of results. 244 Fall, AG, et.al. (2012) The mosquito Aedes (Aedimorphus) vexans arabiensis as a probable vector bridging the West Nile virus between birds and horses in Barkedji (Ferlo, Senegal). Med Vet Entomol. ; 26(1):106-11. Abstract Active catches of adult females of Aedes vexans arabiensis Patton, (Diptera: Culicidae) Patton by nets or aspirator, were conducted in 2003 and 2004 in the vegetation at the edge of temporary ponds in Barkedji, Senegalese Ferlo area. Two hundred and forty-one engorged females were captured, dissected and the gut content adsorbed on a Whatman filter paper and analysed using the enzyme-linked immunosorbent assay (ELISA) technique to determinate the bloodmeal origin. Results indicated that Ae v. arabiensis fed primarily on mammals, including horses (35.7% of the bloodmeals), but also on birds (10%). Moreover, associations between horses and birds accounted for 42% of the mixed bloodmeals. These results show an opportunistic feeding behaviour and suggest that Ae v. arabiensis is a probable vector bridging the West Nile virus between horses and birds hosts in the Ferlo area. 245 García-Bocanegra I, et.al. (2012) Seroprevalence and risk factors associated to West Nile virus in horses from Andalusia, Southern Spain. Vet Microbiol.;160(3-4):341-6. Abstract West Nile virus (WNV) is recognized as an emerging zoonotic pathogen, whose incidence in horses, humans and birds has increased significantly in different European countries in the last decade. A serosurvey study was carried out in non vaccinated horses to determine the geographical distribution of WNV in Andalusia (Southern Spain), and to assess the factors that influence the risk of WNV infection in horses. Antibodies to WNV were detected in 54 out of 510 horses analyzed by a blocking ELISA, of which 36 were confirmed by micro virus neutralization test (7.1%; CI95%: 4.9–9.3). A total of 28 out of the 348 equine herds (8.3%; CI95%: 5.4–11.2) had at least one seropositive animal. A generalized estimating equations model showed that the main risk factors associated to WNV seroprevalence were: number of horses within the holding (low), transport of the horse within the last six months (Yes) and presence of mosquitoes in the holding (Yes). The results demonstrated that WNV circulation in Andalusia was more widespread than previously reported. Besides, the distribution of WNV infections was not homogeneous as significant differences among provinces were observed. The results show the need to improve the active surveillance in Spain, so that the early detection of WNV circulation allows the establishment control measures such as vaccination and implementation of vector control programs during the risk period. 246 Gulat, Baldev R., (2012), et.al. Isolation and genetic characterization of Japanese encephalitis virus from equines in India. J. Vet. Sci. 13(2), 111-118. Abstract Japanese encephalitis (JE) is an important vector-borne viral disease of humans and horses in Asia. JE outbreaks occur regularly amongst humans in certain parts of India and sporadic cases occur among horses. In this study, JE seroprevalence and evidence of JE virus (JEV) infection among horses in Haryana (India) is described. Antibodies against JEV were detected in 67 out of 637 (10.5%) horses screened between 2006 and 2010. Two foals exhibiting neurological signs were positive for JEV RNA by RT-PCR; JEV was isolated from the serum of one of the foals collected on the second day of illness. This is the first report of JEV isolation from a horse in India. Furthermore, a pool of mosquitoes collected from the premises housing these foals was positive for JEV RNA by RT-PCR. Three structural genes, capsid (C), premembrane (prM), and envelope (E) of the isolated virus (JE/eq/India/H225/2009) spanning 2,500 nucleotides (from 134 to 2,633) were cloned and sequenced. BLAST results showed that these genes had a greater than 97% nucleotide sequence identity with different human JEV isolates from India. Phylogenetic analysis based on Eand C/prM genes indicated that the equine JEV isolate belonged to genotype III and was closely related to the Vellore group of JEV isolates from India.

247 Ibarra-Juarez, L, et.al. (2012) Detection of West Nile virus-specific antibodies and nucleic acid in horses and mosquitoes, respectively, in Nuevo Leon State, northern Mexico, 2006-2007. Med Vet Entomol.;26(3):351-4. Abstract In the last 5 years, there has been only one reported human case of West Nile virus (WNV) disease in northern Mexico. To determine if the virus was still circulating in this region, equine and entomological surveillance for WNV was conducted in the state of Nuevo Leon in northern Mexico in 2006 and 2007. A total of 203 horses were serologically assayed for antibodies to WNV using an epitope-blocking enzyme-linked immunosorbent assay (bELISA). Seroprevalences for WNV in horses sampled in 2006 and 2007 were 26% and 45%, respectively. Mosquito collections in 2007 produced 7365 specimens representing 15 species. Culex mosquitoes were screened for WNV RNA and other genera (Mansonia, Anopheles, Aedes, Psorophora and Uranotaenia) were screened for flaviviruses using reversetranscription (RT)-PCR. Two pools consisting of Culex spp. mosquitoes contained WNV RNA. Molecular species identification revealed that neither pool included Culex quinquefasciatus (Say) (Diptera:Culicidae) complex mosquitoes. No evidence of flaviviruses was found in the other mosquito genera examined. These data provide evidence that WNV is currently circulating in northern Mexico and that non-Cx. quinquefasciatus spp. mosquitoes may be participating in the WNV transmission cycle in this region. 248 Klein,Claudia, et.al. (2012) Effect of antimicrobial-containing semen extender on risk of dissemination of contagious equine metritis. J.Am Vet Med Assoc;241:916–921. Abstract Contagious equine metritis is a highly contagious sexually transmitted disease of equids caused by the gram- negative bacterium Taylorella equigenitalis. Although the organism is primarily transmitted via natural mating, transmission through indirect venereal contact with contaminated fomites can also contribute to the spread of this disease. The resulting infection is characterized by endometritis, vaginal discharge, and a severe adverse effect on fertility of mares. Affected mares often recover without treatment and have only short-term infertility, although some mares may harbor the organism in their genital tract for several months or longer without clinical signs; thus, they may serve as a reservoir for infection. 1 Similar to other venereally transmitted pathogens, stallions are subclinical carriers of the causal agent (ie, have no clinical signs); without treatment, they can remain carriers for many months or even years. Recovery of T equigenitalis has been reported from placental tissue2and from the genitalia of colts and fillies, with the organism acquired in utero or through contamination in the birth canal during parturition.3

249 Kuwahara M, Kitai Y, Kondo T, Konishi E. (2012) Survey on antibodies specific for West Nile virus in horses from 2006 to 2010 in Japan. Jpn J Infect Dis.;65(6):553-5. Abstract West Nile virus (WNV) is a zoonotic mosquito-transmitted flavivirus that can cause serious disease and death in horses, humans, and birds. WNV is maintained in a transmission cycle between vector mosquitoes and reservoir birds, whereas humans and horses are deadend hosts in nature. In 1999, WNV was introduced to North America, which was its first appearance in the Western hemisphere. Several years later, WNV spread across the United States and throughout North and South America. Migrating birds are considered to be primarily responsible for the rapid expansion of WNV endemic areas (1). Since WNV is widely distributed throughout many areas of the world (2),WNV infection has become a global public health and veterinary concern. To date, although WNV has not been detected in Japan in nature, the potential for the virus to be introduced by the transportation of WNV-infected vector mosquitoes or reservoir birds from WNV-endemic areas to Japan still exists. Indeed, a study targeting migratory birds revealed a migration route from WNV- endemic areas to Japan (3). 250 Melandri V,et.al. (2012) Serological detection of West Nile virus in horses and chicken from Pantanal, Brazil. Mem Inst Oswaldo Cruz.;107(8):1073-5. Abstract In an effort to detect West Nile virus (WNV) in Brazil, we sampled serum from horses and chickens from the Pantanal region of the state of Mato Grosso and tested for flavivirus-reactive antibodies by blocking ELISA. The positive samples were further confirmed for serological evidence of WNV infection in three (8%) of the 38 horses and one (3.2%) of the 31 chickens using an 80% plaque-reduction neutralisation test (PRNT80). These results provide evidence of the circulation of WNV in chickens and horses in Pantanal. 251 Pennic,k KE, et.al. (2012) Diagnostic sensitivity and specificity of in situ hybridization and immunohistochemistry for Eastern equine encephalitis virus and West Nile virus in formalin-fixed, paraffin-embedded brain tissue of horses. J Vet Diagn Invest.;24: 333-8. Abstract Immunohistochemistry (IHC) and in situ hybridization (ISH) can be used either to detect or to differentiate between Eastern equine encephalitis virus (EEEV) and West Nile virus (WNV) within formalin-fixed, paraffin- embedded (FFPE) brain tissue of horses. To compare the diagnostic sensitivity and specificity of ISH and IHC, FFPE brain tissue from 20 EEEV-positive horses and 16 WNV-positive horses were tested with both EEEV and WNV oligoprobes and EEEV- and WNV-specific antibodies. Reverse transcription polymerase chain reaction (RT-PCR) for detection of EEEV and WNV was used as the gold standard to confirm infection. All horses that tested positive for EEEV by RT-PCR also tested positive by IHC and ISH, except for 1 case that was false-negative by ISH. In contrast, all horses that tested positive for WNV by RT-PCR tested negative by IHC and only 2 horses tested positive by ISH. No false-positives were detected with either method for both viruses. Both IHC and ISH are highly specific and sensitive diagnostic methods to detect EEEV in equine FFPE brain tissues, although neither appear effective for the diagnosis of WNV in equine neurologic cases 252 Ricketts, S, et.al. (2012) Contagious equine metritis organism confirmed in Gloucestershire. Vet Rec. 170(15):398. Abstract Deer A has confirmed the isolation of Taylorella equigenitalis (the contagious equine metritis organism [CEMO]) by identification of the agent using PCR and culture from clitoral swab samples taken from an asymptomatic 15-year-old thoroughbred mare in Gloucestershire. According to the owner, this retired National Hunt race mare has never been covered by a thoroughbred stallion and has never been pregnant, but was unsuccessfully inseminated with semen from a non-thoroughbred stallion last season. This non thoroughbred stallion has also been confirmed positive using PCR and culture 253 Tauro L, Marino B,et.al. Serological detection of St. Louis encephalitis virus and West Nile virus in equines from Santa Fe, Argentina. Mem Inst Oswaldo Cruz. 2012;107(4):553-6. Abstract St. Louis encephalitis virus (SLEV) and West Nile virus (WNV) present ecological and antigenic similarities and are responsible for serious human diseases. In addition, WNV is a significant pathogen in terms of equine health. The purpose of our study was to analyse the seroprevalence of SLEV and WNV in equine sera collected in Santa Fe Province, Argentina. The seroprevalence determined using the plaque reduction neutralisation test was 12.2% for SLEV, 16.2% for WNV and 48.6% for a combination of both viruses. These results provide evidence of the co-circulation of SLEV and WNV in equines in Santa Fe. 254 Yazici Z, Albayrak H, Ozan E, Gumusova S. (2012) The first investigation of west nile virus in horses using real time rt-PCR in middle black sea region in Turkey. J Arthropod Borne Dis.;6(2):151-5. Abstract Background: West Nile Virus (WNV) is a mosquito-borne disease that can cause fatal infection in mammals including humans, dogs, horses, birds and reptiles. Although West Nile Virus is an asymptomatic infection, especially it can cause neurologic disorders in humans and horses. The aim of this study was to the investigate virological presence of WNV in horses in the Black Sea Region of Turkey using real time RT-PCR (rRT-PCR). Methods: Totally, 120 horse sera were collected equally from 4 provinces in Middle Black Sea Region of Turkey and investigated for WNV presence by Taqman based rRT-PCR. Results: WNV nucleic acid was not detected in any horse serum sample. Conclusion: Although obtained result indicated no evidence of WNV– RNA in horses, Black Sea Region of Turkey is one of the suitable places for the WNV infection. For this reason, our research will continue for the determination of the viruses in vectors and susceptible animals such as horses, dogs, etc. 255 Yeh, JY, et.al. (2012) A diagnostic algorithm to serologically differentiate West Nile virus from Japanese encephalitis virus infections and its validation in field surveillance of poultry and horses. Vector Borne Zoonotic Dis. ;12: 372-9 Abstract The detection of West Nile virus (WNV) in areas endemic for Japanese encephalitis virus ( JEV) is complicated by the extensive serological cross-reactivity between the two viruses. A testing algorithm was developed and employed for the detection of anti-WNV antibody in areas endemic for JEV. Using this differentiation algorithm, a serological survey of poultry (2004 through 2009) and horses (2007 through 2009) was performed. Among 2681 poultry sera, 125 samples were interpreted as being positive for antibodies against JEV, and 14 were suspected to be positive for antibodies against undetermined flaviviruses other than WNV and JEV. Of the 2601 horse sera tested, a total of 1914 (73.6%) were positive to the initial screening test. Of these positive sera, 132 sera (5.1%) had been collected from horses that had been imported from the United States, where WNV is endemic. These horses had WNV vaccination records, and no significant pattern of increasing titer was observed in paired sera tests. Of the remaining 1782 positive sera 1468 sera (56.4%) were also found to contain anti-JEV antibodies, and were interpreted to be JEV-specific antibodies by the differentiation algorithm developed in this study. The remaining 314 horses (12.1%) for which a fourfold difference in neutralizing antibody titer could not be demonstrated, were determined to contain an antibody against an unknown (unidentified or undetermined) flavivirus. No evidence of WNV infections were found during the period of this study. 256 Bourgeois, M.A,et.al. (2011) Gene expression analysis in the thalamus and cerebrum of horses experimentally infected with West Nile virus. PLoS One.;6(10):e24371 Abstract Gene expression associated with West Nile virus (WNV) infection was profiled in the central nervous system of horses. Pyrosequencing and library annotation was performed on pooled RNA from the CNS and lymphoid tissues on horses experimentally infected with WNV (vaccinated and naı¨ve) and non-exposed controls. These sequences were used to create a custom microarray enriched for neurological and immunological sequences to quantitate gene expression in the thalamus and cerebrum of three experimentally infected groups of horses (naı¨ve/WNV exposed, vaccinated/WNV exposed, and normal). From the sequenced transcriptome, 41,040 sequences were identified by alignment against five databases. 31,357 good sequence hits (e,1024) were obtained with 3.1% of the sequences novel to the equine genome project. Sequences were compared to human expressed sequence tag database, with 31,473 equine sequences aligning to human sequences (69.27% contigs, 78.13% seed contigs, 80.17% singlets). This indicated a high degree of sequence homology between human and equine transcriptome (average identity 90.17%). Significant differences (p,0.05) in gene expression were seen due to virus exposure (9,020), survival (7,395), and location (7,649). Pathways analysis revealed many genes that mapped to neurological and immunological categories. Involvement of both innate and adaptive components of immunity was seen, with higher levels of expression correlating with survival. This was highlighted by increased expression of suppressor of cytokine signaling 3 in horses exposed to WNV which functions to suppress innate immunity. Pentraxin 3 was most increased in expression for all horses exposed to WNV. Neurological pathways that demonstrated the greatest changes in gene expression included neurotransmitter and signaling pathways. Decreased expression of transcripts in both the glutamate and dopamine signaling pathways was seen in horses exposed to WNV, providing evidence of possible glutamate excitotoxicity and clinical signs associated with decreased dopamine. Many transcripts mapped to non-infectious neurological disease functions, including mental disorders and degenerative neuropathies 257 Burkett-Cadena, Nathan D., et.al. (2011) Winter Biology of Wetland Mosquitoes at a Focus of Eastern Equine Encephalomyelitis Virus Transmission in Alabama, USA. Journal of Medical Entomology, 48(5):967-973. Abstract

At temperate latitudes, vectors and pathogens must possess biological mechanisms for coping with cold temperatures and surviving from one transmission season to the next. Mosquitoes that overwinter in the adult stage have been proposed as winter maintenance hosts for certain arboviruses. In the cases of West Nile virus (family Flaviviridae, genus Flavivirus) and St. Louis encephalitis virus (family Flaviviridae, genus Flavivirus), discovery of infected overwintering females lends support to this hypothesis, but for other arboviruses, in particular Eastern equine encephalomyelitis virus (family Togaviridae, genus Alphavirus, EEEV), overwintering of the virus in mosquito hosts as not been demonstrated. In the current study, we collected overwintering mosquitoes from a focus of EEEV transmission in the southeastern United States to determine whether mosquitoes serve as winter maintenance hosts for EEEV and to document overwintering biologies of suspected vectors. No virus was detected via reverse transcription-polymerase chain reaction of_500 female mosquitoes collected during three winters. Investigation into the winter biologies indicated that Anopheles punctipennis (Say), Culex erraticus (Dyar & Knab), Culex peccator Dyar & Knab, and Uranotaenia sapphirina (Osten Sacken) overwinter as females. Females of these species were collected from hollow trees and emergence traps placed over ground holes. Southern magnolia, Magnolia grandiflora L., trees were preferred overwintering sites of culicine mosquitoes. Emergence from underground overwintering sites peaked in mid- March, when air temperatures reached 18Ð22_C, and the Þrst bloodengorged females of Cx. erraticus and Cx. peccator were collected during this same period. Blood-fed Culex territans Walker females were collected as early as mid-February. This work provides insight into the overwintering biologies of suspected virus vectors at a site of active EEEV transmission and provides limited evidence against the hypothesis thatEEEVpersists through intertransmission periods in overwintering mosquitoes

258 Castillo-Olivares, J,et.al. Antibody response in horses following experimental infection with West Nile Virus lineages 1 and 2. Transbound Emerg Dis.;58(2011):206-12. Abstract West Nile virus (WNV) has re-emerged as an important pathogen for humans and horses, which are considered to be incidental ‘dead-end’ hosts. We have demonstrated that horses are susceptible to experimental infection with WNV and that horses infected with either WNV lineage 1 or lineage 2 elicit a similar antibody profile in serum samples. These data suggest that virus-neutralizing antibody responses persist for longer than WNV- specific IgM levels in serum and that there are not any notable differences in the antibody profile following experimental infection of horses with either WNV lineage 1 and lineage 2 viruses. Furthermore, the duration of IgM appears to be short-lived in horses and may be useful for identifying and differentiating recent infections from previously exposed animals. 259 Erdman, Matthew M., et.al. (2011) Diagnostic and epidemiologic analysis of the 2008–2010 investigation of a multi-year outbreak of contagious equine metritis in the United States. Prev Vet Med, 101: 219– 228 Abstract Contagious equine metritis (CEM) is a highly contagious venereal disease of horses caused by Taylorella equigenitalis. During testing for semen export purposes, a stallion in Kentucky was found to be T. equigenitalis culture positive in December of 2008. This finding triggered an extensive regulatory investigation to search for additional positive horses, determine the extent of the outbreak, identify the potential source of the outbreak, and ultimately return the United States to CEM-free status. The investigation included over 1000 horses located in 48 states. Diagnostic testing found a total of 22 stallions, 1 gelding and 5 mares culture positive for T. equigenitalis. Epidemiologic analysis indicated that all of the positive horses were linked to a single common source, most likely a Fjord stallion imported into the United States in 2000. The T. equigenitalis strain subsequently spread to other stallions via undetermined indirect mechanisms at shared breeding facilities, and to mares via artificial insemination and live breeding. This CEM outbreak and investigation represent the largest ever in the United States based on the number of exposed horses tested and their geographic distribution.

260 Franson, J.C,et.al. (2011) Seroprevalence of West Nile virus in feral horses on Sheldon National Wildlife Refuge, Nevada, United States. Am J Trop Med Hyg.;84(4):637-40. Abstract We screened 1,397 feral horses ( Equus caballus ) on Sheldon National Wildlife Refuge, Nevada, United States, for IgM and IgG against flavivirus during 2004–2006, 2008, and 2009. Positive serum samples were tested for neutralizing antibodies to West Nile virus (WNV) and St. Louis encephalitis virus (SLEV). One animal was positive for antibody against WNV in 2004, but all others tested in 2004–2006 were negative. In 2008 and 2009, we found evidence of increasing seropositive horses with age, whereas seroprevalence of WNV decreased from 19% in 2008 to 7.2% in 2009. No horses were positive for antibody against SLEV. Being unvaccinated, feral horses can be useful for WNV surveillance 261 Hobson-Peters Jet.al. Detection of antibodies to West Nile virus in horses, Costa Rica, 2004. Vector Borne Zoonotic Dis.;11(2011):1081-4 Abstract We conducted a serosurvey for West Nile virus (WNV) infection in equines in Costa Rica in 2004. Antibodies to WNV were detected in 28% of the horses using an epitope blocking ELISA that is specific for WNV. WNV infection was confirmed for a subset of these sera by plaque reduction neutralization tests and Western blot. This is the first evidence of WNV activity in Costa Rica 262 Kitai, Y, Kondo T, Konishi E. Non-structural protein 1 (NS1) antibody-based assays to differentiate West Nile (WN) virus from Japanese encephalitis virus infections in horses: effects of WN virus NS1 antibodies induced by inactivated WN vaccine. J Virol Methods. 2011;171(1):123-8. Abstract Antibodies to non-structural protein 1 (NS1) of West Nile virus (WNV) have been used to differentiate WNV infection from infection by serologically cross-reactive flaviviruses, including Japanese encephalitis virus (JEV), in horses. However, since the inactivated West Nile (WN) vaccine has been reported to induce NS1 antibodies, there is concern about the reliability of using NS1-based assays for testing vaccinated horses. Therefore, the effect of inactivatedWNvaccine-induced antibodies on an epitope-blocking ELISA and complement-dependent cytotoxicity (CDC) assay were investigated. Both assays are based on NS1 antibodies and were established previously to differentiate WNV from JEV infections in horses. Groups of three horses were vaccinated with two or three doses of a commercial inactivated WN vaccine and NS1 antibodies were detected by a conventional ELISA after the second vaccination. Vaccine-induced NS1 antibodies were also detected by blocking ELISA and a CDC assay and affected the ability of these assays to differentiateWNVfrom JEV infections. However, the effectwasless significant in theCDCassay, where use of a low serum concentration ensured effective differentiation. The more efficient detection of infectioninduced antibodies over vaccine-induced antibodies by the CDC assay was potentially attributable to the different IgG isotype profiles of these antibodies 263 Kitai, Y,et.al. Specific antibody responses to West Nile virus infections in horses preimmunized with inactivated Japanese encephalitis vaccine: evaluation of blocking enzyme-linked immunosorbent assay and complement-dependent cytotoxicity assay. Vector Borne Zoonotic Dis.;11(2011):1093-8. Abstract West Nile virus (WNV) and Japanese encephalitis ( JE) virus are distributed separately in the world with some exceptions. There is a concern that WNV may invade into Asia where JE virus exists. On and after such invasion, any differential diagnosis could be complicated by serological crossreactivities. We previously demonstrated experimentally using horses infected with WNV that preimmunization with inactivated JE vaccine considerably affected the ability of neutralization tests and immunoglobulin M (IgM) antibody-capture enzyme-linked immunosorbent assay (ELISA) to diagnose WNV infection. Here, we investigated WNV- specific antibody responses in vaccinated horses using a blocking ELISA and complement-dependent cytotoxicity (CDC) assay to evaluate these two newly developed serodiagnostic methods for WNV infection. Sera previously collected from six experimentally infected horses were used: Three were vaccinated before the infection, whereas the other three remained unvaccinated. WNV-specific antibody responses were successfully detected in the vaccinated and unvaccinated horses using both new methods, except for one vaccinated horse in which responses were not induced, probably as a result of crossprotection induced by JE vaccination. Specific antibody responses were at earliest detected from days 9 to 10 postinfection in the blocking ELISA, whereas the CDC assay provided earlier detection (at days 7–8) in all horses. The time courses of antibody levels were similar between vaccinated and unvaccinated horses in either method, indicating no notable effect of vaccination on detection of specific antibody responses, as far as antibodies were induced. These results indicated that blocking ELISA, but preferably the CDC assay, can be useful for detecting WNV infection in JE- vaccinated horses 264 Kutasi, O., et.al. (2011) Equine Encephalomyelitis Outbreak Caused by a Genetic Lineage 2 West Nile Virus in Hungary. J Vet Intern Med;25:586–591. Abstract Background: The spread of lineage 2 West Nile virus (WNV) from sub-Saharan regions to Europe and the unpredictable change in pathogenicity indicate a potential public and veterinary health threat and requires scientific awareness. Objectives: To describe the results of clinical and virological investigations of the 1st outbreak of a genetic lineage 2 WNV encephalomyelitis in horses. Animals: Seventeen horses with neurologic signs. Methods: Information regarding signalment, clinical signs, and outcome was obtained for each animal. Serology was performed in 15 cases, clinicopathological examination in 7 cases, and cerebrospinal fluid was collected from 2 horses. Histopathology was carried out in 4 horses, 2 of which were assessed for the presence of WNV in their nervous system. Results: WNV neutralizing antibody titers were between 10 and 270 (median, 90) and the results of other serological assays were in agreement with those of the plaque reduction neutralization test. Common signs included ataxia, weakness, asymmetric gait, muscle tremors, hypersensitivity, cranial nerve deficits, and recumbency. Twelve animals survived. Amplicons derived from the infection-positive specimens allowed molecular characterization of the viral strain. Conclusions and Clinical Importance: From our results, we conclude that this outbreak was caused by a lineage 2 WNV strain, even though such strains often are considered nonpathogenic. Neurological signs and survival rates were similar to those reported for lineage 1 virus infections. The disease occurrence was not geographically limited as had been the typical case during European outbreaks; this report describes a substantial northwestern spread of the pathogen

265 Ledermann, JP, et.al. (2011) Evaluation of widely used diagnostic tests to detect West Nile virus infections in horses previously infected with St. Louis encephalitis virus or dengue virus type 2. Clin Vaccine Immunol.;18(2011):580-7 Abstract Primary West Nile virus (WNV) infections can be diagnosed using a number of tests that detect infectious particles, nucleic acid, and specific IgM and/or IgG antibodies. However, serological identification of the infecting agent in secondary or subsequent flavivirus infections is problematic due to the extensive cross- reactivity of flavivirus antibodies. This is particularly difficult in the tropical Americas where multiple flaviviruses cocirculate. A study of sequential flavivirus infection in horses was undertaken using three medically important flaviviruses and five widely utilized diagnostic assays to determine if WNV infection in horses that had a previous St. Louis encephalitis virus (SLEV) or dengue virus type 2 (DENV-2) infection could be diagnosed. Following the primary inoculation, 25% (3/12) and 75% (3/4) of the horses mounted antibody responses against SLEV and DENV-2, respectively. Eighty-eight percent of horses subsequently inoculated with WNV had a WNV-specific antibody response that could be detected with one of these assays. The plaque reduction neutralization test (PRNT) was sensitive in detection but lacked specificity, especially following repeated flavivirus exposure. The WNV-specific IgM enzyme-linked immunosorbent assay (IgM ELISA) was able to detect an IgM antibody response and was not crossreactive in a primary SLEV or DENV response. The WNV-specific blocking ELISA was specific, showing positives only following a WNV injection. Of great importance, we demonstrated that timing of sample collection and the need for multiple samples are important, as the infecting etiology could be misdiagnosed if only a single sample is tested. 266 Lupulovic, D, et.al. (2011) First serological evidence of West Nile virus activity in horses in Serbia. Vector Borne Zoonotic Dis.;11(9):1303-5 Abstract West Nile virus (WNV), the most widely distributed flavivirus worldwide, has lately reemerged in Europe, causing worrisome outbreaks in humans and horses. Serological analysis by enzyme-linked immunoassay and plaque reduction neutralization test showed for the first time in Serbia that 12% of 349 horses presented specific neutralizing WNV antibodies, which in one case also cross-neutralized Usutu virus (USUV). This is the first time that anti-USUV high neutralizing antibody titers are reported in horses. All these data indicate that WNV and USUV are circulating in the region and advise on the convenience of implementing surveillance programs 267 Pauvolid-Corrêa, A, et.al. (2011) Neutralising antibodies for West Nile virus in horses from Brazilian Pantanal. Mem Inst Oswaldo Cruz.;106(4):467-74. Abstract Despite evidence of West Nile virus (WNV) activity in Colombia, Venezuela and Argentina, this virus has not been reported in most South American countries. In February 2009, we commenced an investigation for WNV in mosquitoes, horses and caimans from the Pantanal, Central-West Brazil. The sera of 168 horses and 30 caimans were initially tested using a flaviviruses-specific epitope-blocking enzyme-linked immunosorbent assay (blocking ELISA) for the detection of flavivirus-reactive antibodies. The seropositive samples were further tested using a plaque-reduction neutralisation test (PRNT90) for WNV and its most closely-related flaviviruses that circulate in Brazil to confirm the detection of specific virus-neutralising antibodies. Of the 93 (55.4%) blocking ELISA-seropositive horse serum samples, five (3%) were seropositive for WNV, nine (5.4%) were seropositive for St. Louis encephalitis virus, 18 (10.7%) were seropositive for Ilheus virus, three (1.8%) were seropositive for Cacipacore virus and none were seropositive for Rocio virus using PRNT90, with a criteria of ≥ four-fold antibody titre difference. All caimans were negative for flaviviruses-specific antibodies using the blocking ELISA. No virus genome was detected from caiman blood or mosquito samples. The present study is the first report of confirmed serological evidence of WNV activity in Brazil 268 Timoney, P. J. (2011) Horse species symposium: Contagious equine metritis: An insidious threat to the horse breeding industry in the United States. J. Anim. Sei. 89:1552-1560. Abstract Contagious equine metritis (CFM) has given rise to international concern since it was first recognized as a novel venereal disease of equids in 1977 and the etiologic agent was identified as a previously undescribed bacterium, Taylorella equigenitalis. Horse industry concerns over CEM centered on the ease with which this bacterium could be disseminated, the significance of T. equigenitalis as a cause of short-term infertility in the mare, and the existence of the carrier state in the stallion and the mare. The first known outbreak of CEM in the United States was in Kentucky in 1978. The economic impact on the Thoroughbred industry in the state was substantial. Before 2008, additional small-scale outbreaks occurred in Missouri in 1979, Kentucky in 1982, and Wisconsin in 2006, nearly all attributed to the importation of carrier animals. On each occasion, appropriate measures were taken to eliminate the infection, resulting in the United States regaining its CEM-free status. With the exception of the 1978 occurrence in Kentucky, none of the subsequent outbreaks significantly affected the horse industry. That changed dramatically in 2008, however, after the discovery of a Quarter horse stallion in Kentucky that cultured positive. Subsequent investigations turned up 23 carrier stallions and 5 carrier mares belonging to 11 breeds and located in 8 states. Shipment of infective semen and indirect venereal contact in stallion collection centers through the use of contaminated fomites were major factors in the spread of T. equigenitalis. Trace-back investigations of some 1,005 exposed and carrier stallions and mares in 48 states have failed to identify the origin of this latest CEM event. Neither clinical evidence of CEM nor decreased pregnancy rates were reportedly a feature in infected or exposed mares. In light of these findings, there was some question of whether or not the considerable expense incurred in investigating the latest CEM occurrence was warranted. Regaining CEM-free status for the United States will present considerable challenges

269 Chevalier, V, et.al. (2010) Environmental risk factors of West Nile virus infection of horses in the Senegal River basin. Epidemiol Infect.; 138(11): 1601-9. Abstract In 2005, a serological study was carried out on horses in five ecologically contrasted zones of the Senegal River basin (Senegal) to assess West Nile virus (WNV) transmission and investigate underlying environmental risk factors. In each study zone, horses were randomly selected and blood samples taken. A land-cover map of the five study areas was built using two satellite ETM+ images. Blood samples were screened by ELISA for anti- WNV IgM and IgG and positive samples were confirmed by seroneutralization. Environmental data were analysed using a principal components analysis. The overall IgG seroprevalence rate was 85% (n=367; 95% CI 0.81–0.89). The proximity to sea water, flooded banks and salted mudflats were identified as protective factors. These environmental components are unfavourable to the presence of Culex mosquitoes suggesting that in Senegal, the distribution of the vector species is more limiting for WNV transmission than for the hosts’ distribution. 270 Kitai, Y, Kondo T, Konishi E. (2010) Complement-dependent cytotoxicity assay for differentiating West Nile virus from Japanese encephalitis virus infections in horses. Clin Vaccine Imm.;17: 875-8. Abstract A complement-dependent cytotoxicity (CDC) assay was established to measure antibodies to the West Nile virus (WNV) nonstructural protein 1 (NS1) in horses. Sera collected from a WNV-infected horse mediated lysis of WNV NS1-expressing cells in a dose-dependent manner at higher percentages than sera from a Japanese encephalitis virus (JEV)-infected horse. The percentages of specific lysis for sera diluted 1:10 to 1:80 were <19.8% (assay cutoff) for almost all of the 100 JEV-infected or uninfected horses tested, in contrast to 55 to 76% in WNV-infected horses. Experimental infection revealed that horses became anti-WNV NS1 antibody positive 10 days after WNV infection. This study demonstrated the utility of this assay for differentiating WNV from JEV infections in horses. 271 Loroño-Pino, MA,et.al. Antibodies to influenza and West Nile viruses in horses in Mexico. Vet Rec. 2010;166(1):22-3.

Rios, J.J, et.al. (2010) OAS1 polymorphisms are associated with susceptibility to West Nile encephalitis in horses. PLoS One.;5: e10537. Abstract West Nile virus, first identified within the United States in 1999, has since spread across the continental states and infected birds, humans and domestic animals, resulting in numerous deaths. Previous studies in mice identified the Oas1b gene, a member of the OAS/RNASEL innate immune system, as a determining factor for resistance to West Nile virus (WNV) infection. A recent case-control association study described mutations of human OAS1 associated with clinical susceptibility to WNV infection. Similar studies in horses, a particularly susceptible species, have been lacking, in part, because of the difficulty in collecting populations sufficiently homogenous in their infection and disease states. The equine OAS gene cluster most closely resembles the human cluster, with single copies of OAS1, OAS3 and OAS2 in the same orientation. With naturally occurring susceptible and resistant sub-populations to lethal West Nile encephalitis, we undertook a case-control association study to investigate whether, similar to humans (OAS1) and mice (Oas1b), equine OAS1 plays a role in resistance to severe WNV infection. We identified naturally occurring single nucleotide mutations in equine (Equus caballus) OAS1 and RNASEL genes and, using Fisher’s Exact test, we provide evidence that mutations in equine OAS1 contribute to host susceptibility. Virtually all of the associated OAS1 polymorphisms were located within the interferon-inducible promoter, suggesting that differences in OAS1 gene expression may determine the host’s ability to resist clinical manifestations associated with WNV infection 272 Venter, M, Swanepoel R. West Nile virus lineage 2 as a cause of zoonotic neurological disease in humans and horses in southern Africa. Vector Borne Zoonotic Dis. ;10 (2010): 659-64. Abstract West Nile virus (WNV) is widely distributed in South Africa, but since a few cases of neurological disease have been reported from this region, endemic lineage 2 strains were postulated to be of low virulence. Several cases of nonfatal encephalitis in humans as well as fatal cases in a foal, dog, and ostrich chicks have, however, been associated with lineage 2 WNV in South Africa. The pathogenesis of lineage 2 WNV strains was investigated using mouse neuroinvasive experiments, gene expression experiments, and genome sequence comparisons which indicated that lineage 2 strains that are highly pathogenic exist. To determine whether cases of WNV were being missed in South Africa, horses with fever and neurological disease were investigated. Several cases of WNV were identified, all associated with severe neurological disease, 85% of which had to be euthanized or died. All cases positive by RT-PCR were shown to belong to lineage 2 WNV by DNA sequencing and phylogenetic analysis. Two cases of occupational infection were investigated, including a case of zoonotic transmission to a veterinarian who performed an autopsy on one of the horses as well as a laboratory infection after a needle stick injury with a neuroinvasive lineage 2 strain. Both resulted in neurological disease. Cytokine expression was investigated in the second case to assess the immunopathogenesis of WNV. Collectively, these studies suggest that lineage 2 WNV may be significantly under estimated as a cause of neurological disease in South Africa. 273 Wang, Zhongming, et.al. (2010) Dissemination of western equine encephalomyelitis virus in the potential vector, Culex pipiens pallens. Journal of Vector Ecology, 35: 313-317 Abstract

Two western equine encephalomyelitis virus (WEEV) strains have been isolated in China. Our previous studies have verified that the mosquito Culex pipiens pallens Coquillett (Diptera: Culicidae) infected with WEEV was capable of transmitting this arbovirus, but it was not clear how the sequential multiplication and spread of virus occurred within the mosquito. In this study, we observed the distribution of WEEV antigen in orally-infected Cx. p. pallens by immunohistochemistry in order to better understand the initial infection, dissemination, and transmission of WEEV in the potential vector. Orally-infected WEEV dissemination varied within the different tissues of Cx. p. pallens, with virus antigen consistently observed in the salivary glands, foregut, midgut epithelial cells, Malpighian tubules, hindgut, and ovarian follicles of some individuals after various days of extrinsic incubation. We suggest that Cx. p. pallens, the potential vector of WEEV, has the ability to harbor the virus through the alimentary system, and the midgut epithelial cell may be the initial site of WEEV replication after ingestion of a viremic blood meal

274 Alonso-Padilla, J,et.al. (2009) The continuous spread of West Nile virus (WNV): seroprevalence in asymptomatic horses. Epidemiol Infect.;137(8):1163-8. Abstract West Nile virus (WNV) was probably introduced in southern and northern Mexico from the USA in two independent events. Since then, WNV activity has been reported in several Mexican states bordering the USA and the Gulf of Mexico, but disease manifestations seen there in humans and equids are quite different to those observed in the USA. We have analysed WNV seroprevalence in asymptomatic, unvaccinated equids from two Mexican states where no data had been previously recorded. WNV IgG antibodies were detected in 31-6% (91/288) of equine sera from Chiapas and Puebla states (53-3% and 8*0%, respectively). Analysis by plaque reduction neutralization test (PRNT) showed good specificity (99-4%) and sensitivity (84-9%) with the ELISA results. Further analyses to detect antibodies against three different flaviviruses (WNV, St Louis encephalitis virus, Ilheus virus) by haemagglutination inhibition (HI) tests on a subset of 138 samples showed that 53 % of the 83 HI-positive samples showed specific reaction to WNV. These data suggest continuous expansion of WNV through Mexico. 275 Komar N, Langevin S, Monath TP. Use of a surrogate chimeric virus to detect West Nile virus- neutralizing antibodies in avian and equine sera. Clin Vaccine Imm. 2009;16(1):134-5. Abstract A chimeric yellow fever virus/West Nile virus (WNV) was compared to WNV alone as a biosafety level 2 reagent in the plaque reduction neutralization test for determining WNV infection histories. Concordance was 96.3% among 188 avian and equine serum samples. Neutralizing antibody titers were frequently more than twofold lower with the chimera. 276 Pradel, J, et.al. (2009) Risk factors for West Nile virus seropositivity of equids in Guadeloupe. Prev Vet Med.;92(1-2):71-8. Abstract In Guadeloupe, West Nile virus (WNV) activity was first observed in equids in 2002, and a high seroprevalen- ce was found in 2003. The objective of our study was to determine individual and environmental factors associated with the risk of WNV seropositivity during 2002–2003. Fieldwork was conducted to retrospectively determine the location of equids at the time of virus circulation and to collect information regarding environ- mental and individual variables. Sera were collected from 369 equids out of an estimated total population of less than 500. Thirty-four environmental and individual variables were investigated. Equids had a higher risk (p < 0.001) for WNV seropositivity if they lived within the proximity ‘‘distance less than 1.5 km’’ of marshes or swamp forests ‘‘a large freshwater formation behind mangroves’’ or if they remained outside after dusk. Equids living within the proximity of ouassous shrimp (Macrobrachium rosenbergii) basins or sugar cane fields had a lower risk (p < 0.001) forWNVseropositivity. These results confirm that WNV circulation is more likely in the humid coastal areas of Guadeloupe. The identification of risk factors is useful for predicting future emergence sites of WNV in the archipelago and other Neotropical islands, and to better target sentinel surveillance in the region. 277 Rios, LM,et.al. (2009) Environmental risk factors associated with West Nile virus clinical disease in Florida horses. Med Vet Entomol;23(4): 357-66. Abstract The objective of this study was to examine the extrinsic risk factors of West Nile virus (WNV) clinical disease in Florida horses as established from confirmed and negative horses tested within the state from 2001 to 2003. An Arboviral Case Information Form (ACF) was submitted by a referring veterinarian at the time of testing to the Florida Department of Agriculture and Consumer Services on every horse suspected of a viral encephalitis in Florida. A follow-up survey that focused on arbovirus prevention and farm ecology was created and mailed to the owner of each tested horse. Data from the follow-up survey indicated peak WNV prevalence in the late summer months in Florida. Quarter horses were the most commonly affected breed. The WNV vaccine was highly protective and natural water on the property also had a protective association. Factors that increased the risk of WNV to horses were the use of fans and a stable construction of solid wood or cement. Some risk indicators were dead birds on the property and other ill animals on the property. Data from this retrospective study have helped identify factors associated with WNV transmission in equines in Florida. Horses that have not been vaccinated and show clinical signs of arboviral infection from June to November should be tested for WNV. Horses that have been vaccinated and show clinical signs should be tested when the vaccination was administered within 1 month or greater than 6 months prior to the onset of clinical symptoms associated with WN infection. 278 Shirafuji, H,et.al. (2009) Antibody responses induced by experimental West Nile virus infection with or without previous immunization with inactivated Japanese encephalitis vaccine in horses. J Vet Med Sci.;71(7):969-74. Abstract A group of horses immunized with inactivated Japanese encephalitis (JE) vaccine (JE-Immune Group) and a group of nonimmunized horses (Non-Immune Group) were infected with West Nile virus (WNV). After WNV infection, neutralizing (Nt) antibody (Ab) titers to WNV were higher than those to JE virus (JEV) in the Non- Immune Group, but the NtAb titers to JEV were higher than those to WNV during most of the post-challenge observation period in the JE-Immune Group. Immunoglobulin M (IgM) Abs to WNV tested positive in the Non-Immune Group but negative in the JE-Immune Group, except for in one horse. These results suggest that diagnosis of WNV infection in JE-immunized horses requires serological tests for NtAb and IgM titers to both WNV and JEV. 279 Valero, Nereida, Anaı´s Nery, et.al. (2009) Antagonistic Effect of Luzindole in Mice Treated with Melatonin During the Infection with the Venezuelan Equine Encephalomyelitis Virus. Neurochem Res 34:268–273 Abstract The effect of Luzindole (LZ) in mice treated with melatonin (MEL) during the infection with the Venezuelan equine encephalomyelitis (VEE) virus was examined. Melatonin (500 lg/Kg b.w.) was administered daily 3 days before and 5 days after the infection. Luzindole (5 mg/Kg b.w.) was injected intraperitoneally 3 days before (pre-infection) or 5 days after (post-infection) the infection. Mortality rates in the infected mice treated both with MEL and LZ were higher than in those treated with MEL alone in which the lowest brain and serum viral titers were detected. On the third post-infection day, viral titers of the MEL + VEE + LZ (pre-infection) group were higher than those of the remainder groups. On the fifth day, viral titers in infected mice were similar to those of the MEL + VEE + LZ (pre-infection) group, but higher than those detected in the MEL + VEE + LZ (post-infection). In conclusion, the protective effect of MEL in mice infected with VEE virus was inhibited by LZ suggesting that this protection is mediated by MEL receptors

280 Venter, M, et.al. (2009) Lineage 2 west nile virus as cause of fatal neurologic disease in horses, South Africa. Emerg Infect Dis.;15(6):877-84. Abstract Serologic evidence suggests that West Nile virus (WNV) is widely distributed in horses in southern Africa. However, because few neurologic cases have been reported, endemic lineage 2 strains were postulated to be nonpathogenic in horses. Recent evidence suggests that highly neuroinvasive lineage 2 strains exist in humans and mice. To determine whether neurologic cases are being missed in southern Africa, we tested 80 serum or brain specimens from horses with unexplained fever (n = 48) and/or neurologic signs (n = 32) for WNV. From March 2007 through June 2008, using reverse transcription–PCR (RT-PCR) and immunoglobulin (Ig) M ELISA , we found WNV RNA or IgM in 7/32 horses with acute neurologic disease; 5 horses died or were euthanized. In 5/7 horses, no other pathogen was detected. DNA sequencing for all 5 RT-PCR–positive cases showed the virus belonged to lineage 2. WNV lineage 2 may cause neurologic disease in horses in southern Africa. 281 Ward, MP,et.al. (2009) Environmental risk factors for equine West Nile virus disease cases in Texas. Vet Res Commun. Jun;33(5):461-71. Abstract West Nile Virus (WNV) was first detected in the Texas equine population during June 2002. Infection has since spread rapidly across the state and become endemic in the equine population. Environmental risk factors associated with equine WNV attack rates in Texas counties during the period 2002 to 2004 were investigated. Equine WNVattack rates were smoothed using an empirical Bayesian model, because of the variability among county equine populations (range 46−9,517). Risk factors investigated included hydrological features (lakes, rivers, swamps, canals and river basins), land cover (tree, mosaic, shrub, herbaceous, cultivated and artificial), elevation, climate (rainfall and temperature), and reports of WNV-positive mosquito and wild bird samples. Estimated county equine WNV attack rate was best described by the number of lakes, presence of broadleaf deciduous forest, presence of cultivated areas, location within the Brazos River watershed, WNV-positive mosquito status and average temperature. An understanding of environmental factors that increase equine WNV disease risk can be used to design and target disease control programs. 282 Ward, MP. (2009) Equine West Nile virus disease occurrence and the Normalized Difference Vegetation Index. Prev Vet Med.;88(3):205-12. Abstract The association between the Normalized Difference Vegetation Index (NDVI) and periods of above- or below- average reported cases of equine West Nile virus encephalomyelitis, reported in Texas between 2002 and 2004, was investigated. A time-series of case reports, using a biweekly window, was constructed. Because of the disparity in number of cases reported (1698, 672 and 101 in 2002, 2003 and 2004, respectively), data were standardized by calculating the number of cases reported during each biweekly period as a ratio of the annual average number of cases reported. Themean NDVI (0.439) in Texas in biweekly periods in which cases were reported was significantly higher (P < 0.001) than themean NDVI (0.396) in periods in which cases were not reported. The best-fitting model of standardized case ratios included the mean NDVI in the preceding 4-week period. This associationwas further investigated in the two ecological regions of Texas inwhich most cases were reported during the study period—Prairies and Lakes, and the Panhandle Plains. Standardized case ratios in the Prairies and Lakes ecoregion were best predicted by NDVI estimated 19–20 weeks previously, whereas standardized case ratios in the Panhandle Plains region were most strongly associated with NDVI estimated 1–4 weeks previously, indicating that the temporal lag between appropriate environmental conditions and resulting increased risk of WNV transmission can vary in different regions. The associations identified could be useful in an early-warning system of increased disease risk. 283 Yuriadi. et.al. (2009) Kajian molekuler daerah D-Loop parasial Deoxyribonucleic acid (DNA) mitokondria kuda (Equus caballus) asli Priangan.- Jurnal Sain Veteriner, 27: 67-74. Abstract Kuda Priangan adalah salah satu dari tiga kuda asli Indonesia. Penelitian ini bertujuan untuk menhkaji daerah nonkoding (D-loop) DNA mitokondria kuda asli Priangan. Sebanyak lima sampel darah kuda likal priangan diambil dari wilayah Kabupaten Indramayu dan Bandung Jawa Barat. Amplifikasi wilayah nonkoding (D-loop) dilakukan dengan menggunakan primer 5’-CGCACATTACCCTGGTCTTG-3’ dan 5’GAACCAGATGCCAGGTATG-3’, masing-masing sebagai forward dan reverses primer. Amplikon di karakterisasi secara elektroforesis menggunakan gel agarose 1.2%. Pemurnian amplikon dilakukan dengan kolom kromatografi GFX kemudian dilakukan sequensing untuk menentukan sequen DNA-nya. Keragaman genetik sequen DNA daerah non penyandi (D-loop) parsial kuda priangan dianalisis dengan program MEGA versi 4. Hasil penelitian menunjukkan sebelas posisi nukleotida yang polimorfik pada sekuen D-loop yang terbaca sepanjang 355 nt. Jarak genetik yang dihitung dengan model Kimura dua parameter berkisar antara 0% sampe 15.02% dan rata-rata 7.51%. Analisis filogenetik menunjukkan bahwa pada priangan merupakan anggota species Equus caballus.

284 Catherine Ceˆtre-Sossah, et.al. (2008) Development and evaluation of a real-time quantitative PCR assay for Culicoides imicola, one of the main vectors of bluetongue (BT) and African horse sickness (AHS) in Africa and Europe. Research in Veterinary Science, 85: 372–382. Abstract The current microscopy method for identifying the Culicoides imicola Kieffer, 1913 species can be time and labour intensive. There is a need for the development of a rapid and quantitative tool to quantify the biting midges C. imicola ss in light trap catches. A reproducible and sensitive real-time polymerase chain reaction method that targets the internal transcribed spacer (ITS-1) of ribosomal DNA of C. imicola ss species was developed. This real-time PCR assay was first performed on 10-fold serial dilutions of purified plasmid DNA containing specific C. imicola ss ITS-1. It was then possible to construct standard curves with a high correlation coefficient (r2 = 0.99) in the range of 10_2–10_8 ng of purified DNA. The performances of this PCR were evaluated in comparison with morphological determination on Culicoides trapped along the Mediterranean coastal mainland France. ROC statistical analysis was carried out using morphology as gold standard and the area under the ROC curve had a satisfactory value of 0.9752. The results indicated that this real-time PCR assay holds promise for monitoring C. imicola ss population in both surveillance and research programmes because of its good specificity (92%) and sensitivity (95%). 285 Davis, EG, et.al. (2008) Investigation of antigen specific lymphocyte responses in healthy horses vaccinated with an inactivated West Nile virus vaccine. Vet Imm Immunopathol.;126:293-301. Abstract West Nile virus (WNV) is a single-stranded, enveloped RNA virus capable of causing encephalitic disease in horses. Unvaccinated horses are at risk for developingWNV disease in endemic geographic regions. Effective vaccination reduces disease frequency and diminishes disease severity in vaccinated individuals that become infected with WNV. Recent data indicate CD4+ lymphocytes are required for effective protection against disease; in particular, cross talk between CD4+ and CD8+ lymphocytes must be functional. The objective of this project was to investigate immune responses in horses throughout a series of three vaccinations using a commercial inactivated vaccine under natural conditions. Immune responses to vaccination were determined by neutralizing antibody titers with plaque reduction neutralization test (PRNT), IgM titer (capture ELISA), WNV specific antibody Ig subclass responses, WNV lymphocyte proliferative responses and intracellular cytokine expression. Horses were vaccinated with a series of three vaccines at 3-week intervals using an inactivated product. An initial measure of immune activation following vaccination was determined by evaluating changes in lymphocyte cytokine expression. Interferon (IFN) gamma and interleukin (IL)-4 expressing CD4+ lymphocytes significantly increased 14 days following initial vaccination compared to unvaccinated horses (P < 0.05). IFN-gamma expressing CD8+ lymphocytes also increased and remained elevated for 110 days. Antigen specific lymphocyte proliferative responses were significantly increased up to 90 days following the third vaccination (P < 0.05). As expected, vaccinated horses produced increased neutralizing antibody based on PRNT data and WNV antigen-specific Ig subclass responses compared with unvaccinated horses (P < 0.05). Our data indicate that WNV vaccination with an inactivated product effectively induced an antigen-specific antibody responses, as well as CD4+ and CD8+ lymphocyte activation. 286 El Garch H, et.al. (2008) A West Nile virus (WNV) recombinant canarypox virus vaccine elicits WNV-specific neutralizing antibodies and cell-mediated immune responses in the horse. Vet Immunol Immunopathol.;123(3-4):230-9. Abstract Successful vaccination against West Nile virus (WNV) requires induction of both neutralizing antibodies and cell-mediated immune responses. In this study, we have assessed the ability of a recombinant ALVAC1-WNV vaccine (RECOMBITEK1 WNV) to elicit neutralizing antibodies and virus-specific cell-mediated immune responses in horses. In addition, we examined whether prior exposure to ALVAC1-WNV vaccine would inhibit B and cell-mediated immune responses against the transgene product upon subsequent booster immunizations with the same vaccine. The results demonstrated that the recombinant ALVAC1-WNV vaccine induced neutralizing antibodies and prM/E insert-specific IFN-g+ producing cells againstWNVin vaccinated horses. Prior exposure to ALVAC1-WNV vaccine did not impair the ability of horses to respond to two subsequent booster injections with the same vaccine, although anti-vector-specific antibody and cell-mediated immune responses were induced in vaccinated horses. This report describes, for the first time, the induction of antigen- specific cell-mediated responses following vaccination with an ALVAC1 virus recombinant vaccine encoding WNVantigens. Moreover, we showed that bothWNV-specific IFN-g producing cells and anti-WNV neutralizing antibody responses, are not inhibited by subsequent vaccinations with the same vector vaccine 287 Epp, T, Waldner C, Corrigan R, Curry P. (2008) Public health use of surveillance for West Nile virus in horses: Saskatchewan, 2003-2005. Transbound Emerg Dis.;55:411-6. Abstract West Nile virus (WNV) infection in horses was first reported in Canada in 2001 and in the province of Saskatchewan in 2002. This paper outlines the surveillance results of WNV in Saskatchewan horses from 2003 to 2005 and describes the usefulness of its inclusion in an integrated surveillance program in Saskatchewan. The number of human and horse cases was highest in 2003, the epidemic year and then substaintially lower in 2004 and 2005. Horses provided additive information about WNV activity in rural areas with low human population, however, this required willingness and active participation by veterinarians and horse owners. Vaccination impedes the future use of horses in WNV surveillance for public health or veterinary purposes; however, for zoonoses where no vaccination is available, domestic animals would be useful components for surveillance. Integration of surveillance data from human and animal health provide the benefit of a more complex epidemiological picture that can be used to improve public health 288 Fitzgibbon, J.E., J.-L. Sagripanti, et.al. (2008) Analysis of the survival of Venezuelan equine encephalomyelitis virus and possible viral simulants in liquid suspensions. J of Applied Mic 105: 1477–1483. Abstract Aims: To compare the inactivation rate of Venezuelan equine encephalomyelitis (VEE) virus in liquids to that of Sindbis virus (SV, another alphavirus) and to a bacteriophage (MS2) generally used as a viral simulant in the development of countermeasures in biodefense. Methods and Results: Viruses were inoculated into liquids and viral titres were determined at various times postinoculation. The viruses were stable in distilled- deionized (dd) water at 4_C during the 21 days of the study. The inactivation rates of VEE and SV in dd water at 21 and 30_C were very similar (between 0Æ12 and 0Æ14 log10 per day), while MS2 was three-fold slower. In tap water (chlorine content between 4 and 5 ppm) at 21_C, VEE and SV were inactivated at twice the rate measured in dd water. Conclusions: The inactivation rates of VEE and SV were similar to each other and faster than MS2 in all liquids tested. Significance and Impact of the Study: VEE is likely to remain viable for many days after release into water, snow, or even chlorinated tap water. SV can be used to estimate the persistence of VEE in liquids, but using MS2 as a simulant would overestimate of the stability of VEE.

289 Hobson-Peters, J,et.al.( 2008) A glycosylated peptide in the West Nile virus envelope protein is immunogenic during equine infection. J Gen Virol.;89(Pt 12):3063-72. Abstract Using a monoclonal antibody directed to domain I of the West Nile virus (WNV) envelope (E) protein, we identified a continuous (linear) epitope that was immunogenic during WNV infection of horses. Using synthetic peptides, this epitope was mapped to a 19 aa sequence (WN19: E147– 165) encompassing the WNV NY99 E protein glycosylation site at position 154. The inability of WNV-positive horse and mouse sera to bind the synthetic peptides indicated that glycosylation was required for recognition of peptide WN19 by WNV-specific antibodies in sera. N-linked glycosylation of WN19 was achieved through expression of the peptide as a C- terminal fusion protein in mammalian cells and specific reactivity of WNV-positive horse sera to the glycosylated WN19 fusion protein was shown by Western blot. Additional sera collected from horses infected with Murray Valley encephalitis virus (MVEV), which is similarly glycosylated at position E154 and exhibits high sequence identity to WNV NY99 in this region, also recognized the recombinant peptide. Failure of most WNV- and MVEV-positive horse sera to recognize the epitope as a deglycosylated fusion protein confirmed that the N-linked glycan was important for antibody recognition of the peptide. Together, these results suggest that the induction of antibodies to the WN19 epitope during WNV infection of horses is generally associated with E protein glycosylation of the infecting viral strain. 290 Macini, P, Squintani G,et.al. (2008) Detection of West Nile virus infection in horses, Italy, September 2008. Euro Surveill.;13(39). pii: 18990 Abstract Six confirmed and five suspected cases of West Nile virus infection in horses have been reported in the vicinity of Ferrara in Italy. To verify the diffusion of viral circulation and to prevent the spread of disease, the regional authorities of Emilia-Romagna adopted a special plan of West Nile fever surveillance 291 Magnarelli, LA,et.al. Serum antibodies to West Nile virus in naturally exposed and vaccinated horses. J Med Microbiol. 2008; 57(Pt 9):1087-93 Abstract A polyvalent ELISA and plaque reduction neutralization tests (PRNTs) were used to measure serum antibodies to West Nile virus (WNV) in horses naturally exposed to or vaccinated against this flavivirus in Connecticut and New York State, USA. Relying on a PRNT as a ‘gold standard’, the main objective was to validate a modified ELISA containing a recombinant WNV envelope protein antigen. It was also important to assess specificity by testing sera from horses that had other, undiagnosed illnesses. Sera for the latter study were obtained from 43 privately owned horses during 1995–1996. Analyses by an ELISA and a PRNT confirmed the presence of WNV antibodies in 21 (91 %) of 23 sera from naturally exposed horses and in 85% of the 20 vaccinated subjects; overall results for both study groups were highly concordant (91% agreement). Humoral responses of naturally exposed and immunized horses were similar. Both serological tests were useful in confirming past infections with WNV, but there was no evidence that horses with undiagnosed illnesses were exposed to WNV prior to a 1999 outbreak in Connecticut, USA. 292 Mongoh, M. Ndiva, et.al. (2008) The economic impact of West Nile virus infection in horses in the North Dakota equine industry in 2002. Trop Anim Health Prod 40:69–76 Abstract This study estimated economic impacts associated with the West Nile virus (WNV) outbreak in horses for North Dakota in 2002.The 2002 epidemic in the United States was the largest meningoencephalitis epidemic reported in the Western Hemisphere. Over 15,257 horse cases were reported in 43 states with most cases occurring in central United States. North Dakota reported over 569 horse cases, with a mortality rate of 22%. The total costs incurred by the state were approximately US$1.9 million. The costs incurred by horse owners were about US$1.5 million. Of the US$1.5 million, about US$781,203 and US$802,790 were spent on medical costs and losses due to inability to use animals because of the disease, respectively. Medical costs included the cost of vaccinating 152 horses, and the treatment costs for 345 horses which were US$4,803 and US$524,400 respectively. Costs associated with mortality were US$252,000 for the 126 horses which died of WNV. The state government spent US* $400,000 on WNV monitoring, control, and surveillance under the WNV-control program in 2002. Despite these conservative estimates, the data suggest that economic costs attributable to WNV epidemic to horse owners in North Dakota were substantial.

293 Nielsen, CF,et.al. (2008) High subclinical West Nile virus incidence among nonvaccinated horses in northern California associated with low vector abundance and infection. Am J Trop Med Hyg. ;78(1):45-52. Abstract Although horse cases frequently are reported during West Nile virus (WNV) outbreaks, few investigations have focused on the epidemiology of this transmission. From April to October 2003 to 2005, mosquito abundance and infection were monitored 3 days per week at an equine research facility at the University of California, Davis. Thirty-two nonvaccinated horses enrolled as controls in a vaccine study were bled monthly, and their serum was tested for evidence of WNV infection by plaque reduction neutralization test (PRNT). In 2004, one positive Culex pipiens pool was associated with a single horse that presented with confirmed WNV disease in late September. The annual incidence of clinical and subclinical WNV infection in the nonvaccinated horses was 16%, with an apparent to inapparent ratio of 1:4 among infected horses. In 2005, two Culex tarsalis and two Cx. pipiens WNV-positive pools were associated with an equine infection incidence of 62%, with an apparent to inapparent ratio of 1:17. The majority (79%) of 70 bloodengorged Cx. pipiens fed on birds and the remaining on equines (21%). Conversely, Cx. tarsalis fed primarily on equines (n_23, 74%), followed by birds (n_7, 23%) and 1 (3%) fed on a lagomorph. These data indicated that nonvaccinated horses were a sensitive indicator of WNV activity and that their risk of infection was associated with the presence of infection in Cx. pipiens and Cx. tarsalis, which served as both enzootic and bridge vectors amplifying WNV among birds and transmitting WNV to horses. 294 Rochlin I,et.al. (2008) Comparative analysis of distribution and abundance of West Nile and eastern equine encephalomyelitis virus vectors in Suffolk County, New York, using human population density and land use/cover data. J Med Entomol.;45(3):563-71. Abstract Five years of CDC light trap data from Suffolk County, NY, were analyzed to compare the applicability of human population density(HPD)and land use/cover (LUC)classiÞcation systems to describe mosquito abundance and to determine whether certain mosquito species of medical importance tend to be more common in urban (deÞned by HPD) or residential (deÞned by LUC) areas. Eleven study sites were categorized as urban or rural using U.S. Census Bureau data and byLUC types using geographic information systems (GISs). Abundance and percent composition of nine mosquito taxa, all known or potential vectors of arboviruses, were analyzed to determine spatial patterns. By HPD deÞnitions, three mosquito species, Aedes canadensis (Theobald), Coquillettidia perturbans (Walker), and Culiseta melanura (Coquillett), differed signiÞcantly between habitat types, with higher abundance and percent composition in rural areas. Abundance and percent composition of these three species also increased with freshwater wetland, natural vegetation areas, or a combination when using LUC deÞnitions. Additionally, two species, Ae. canadensis and Cs. melanura, were negatively affected by increased residential area. One species, Aedes vexans (Meigen), had higher percent composition in urban areas. Two medically important taxa, Culex spp. and Aedes triseriatus (Say), were proportionally more prevalent in residential areas by LUC classiÞcation, as was Aedes trivittatus (Coquillett). Although HPD classiÞcation was readily available and had some predictive value, LUC classiÞcation resulted in higher spatial resolution and better ability to develop location speciÞc predictive models. 295 Wagner, B,et.al. (2008) Monoclonal antibodies to equine IgM improve the sensitivity of West Nile virus-specific IgM detection in horses. Vet Imm. Immunopat.;122: 46-56. Abstract West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNVspecific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNVencephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the three anti- IgM antibodies. The anti-IgM 1-22 mAb correctly identified all NVSL samples. Both the polyclonal antibody and monoclonal anti- IgM 2B-63 identified eight out of ten samples correctly. The three assays were then compared using serum samples from clinically healthy animals (n = 33) and horses with neurological signs (n = 21). High Spearman rank correlations (0.76–0.86) were found among the ELISA results. Inter-test agreements (weighted kappa) for assay interpretation resulted in strong agreement (0.95) of the results obtained by the mAbs and moderate agreements when monoclonal and polyclonal anti-IgM-based assays were compared. To determine the analytical sensitivities of anti-WNV IgM detection, serial dilutions of WNV IgM-positive serum samples were analyzed. The highest sensitivity was obtained by using the anti-IgM 1-22 mAb to capture IgM from equine serum. In conclusion, the use of monoclonal anti-IgM antibodies can improve the sensitivity of IgM detection in the acute phase of WN disease 296 Ward, MP, Scheurmann JA. (2008) The relationship between equine and human West Nile virus disease occurrence. Vet Microbiol.;129(3-4):378-83. Abstract Cases of human and equineWest Nile virus (WNV) disease reported in Texas in 2002 were analyzed to assess their temporal relationship. For each human case with a known residential location, the closest equine case (within a 5 km radius) was selected. A total of 80 human–equine case pairs were identified, 51 (64%) of which were located in urban areas. Dates-of-onset of human and equine cases were positively correlated (rSP = 0.494, P < 0.001). Although overall there was no significant (P = 0.207) difference between the dates-of-onset of human and equine cases, in urban areas of Texas equine cases were reported significantly (P = 0.011) earlier (August 7) than corresponding human cases (August 19). Monitoring equine populations that are susceptible to WNVdisease within close proximity to urban human populations might be useful for predicting disease risk in human populations. 297 Wittich, CA, et.al. (2008) Identification of hyperendemic foci of horses with West Nile virus disease in Texas. Am J Vet Res.;69(3):378-84. Abstract Objective—To determine whether West Nile virus (WNV) disease hyperendemic foci (hot spots) exist within the horse population in Texas and, if detected, to identify the locations. Sample Population—Reports of 1,907 horses with WNV disease in Texas from 2002 to 2004. Procedures—Case data with spatial information from WNV epidemics occurring in 2002 (1,377 horses), 2003 (396 horses), and 2004 (134 horses) were analyzed by use of the spatial scan statistic (Poisson model) and kriging of empirical Bayes smoothed county attack rates to determine locations of horses with WNV disease in which affected horses were consistently (in each of the 3 study years) clustered (hyperendemic foci, or hot spots). Results—2 WNV hot spots in Texas, an area in northwestern Texas and an area in eastern Texas, were identified with the scan statistic. Risk maps of the WNV epidemics were qualitatively consistent with the hot spots identified. Conclusions and Clinical Relevance— WNV hot spots existed within the horse population in Texas (2002 to 2004). Knowledge of disease hot spots allows disease control and prevention programs to be made more efficient through targeted surveillance and education 298 Epp, T, Waldner C, West K, Townsend H. (2007) Factors associated with West Nile virus disease fatalities in horses. Can Vet J.;48(11):1137-45. Abstract In 2003, the occurrence and location of horses with clinical signs of West Nile virus infection were identified in the southern portion of Saskatchewan with the help of veterinarians, owners, and the regional laboratory. A total of 133 clinical cases were reported between July 30 and September 19, 2003; however, postseason surveillance suggests that the number of cases was underestimated. The case fatality rate was 43.8% (95% CI 35.2, 52.4). Factors associated with fatality in clinical cases included sex, week of onset of clinical signs, and coat color. Reported clinical cases clustered within regional health authority districts, suggesting regional differences in geographic factors, potentially including climate and mosquito control, that could contribute to the risk of disease. However, most of the variation in the risk of fatality in clinical cases is explained at the individual level rather than the Regional Health Authority level, which suggests the outcome of clinical disease is primarily determined by characteristics of, or management factors affecting, the individual horse 299 Epp, T, Waldner C,et.al. (2007) Seroprevalence and risk factors for infection with West Nile virus in Saskatchewan horses, 2003. Can J Vet Res.;71(4):256-63. Abstract The primary objectives of this study were to determine the seroprevalence of West Nile virus (WNV) infection of horses in Saskatchewan in 2003 and to identify risk factors for the infection. Blood samples were collected in August and October from 212 horses in 20 herds in 5 geographic zones. After accounting for within-herd clustering, the proportion of horses that had been infected with WNV, as determined by IgG and IgM antibody response, was 55.7% (95% confidence interval, 44.9% to 65.8%). The proportion of antibody-positive horses differed among herds (0% to 100%) and across ecoregions (20% to 76%). Horses in southern ecoregions were more likely to have either IgM antibodies or IgG concentrations suggesting infection than were horses in northern ecoregions. The use of mosquito-control measures was associated with decreased risk. After accounting for ecoregion, there was no difference between recipients of an inactivated WNV vaccine and nonrecipients in the occurrence of antibodies reflecting natural infection. 300 Kitai, Y, et.al. (2007) Epitope-blocking enzyme-linked immunosorbent assay to differentiate west nile virus from Japanese encephalitis virus infections in equine sera. Clin Vaccine Imm.;14:1024-31. Abstract West Nile virus (WNV) is now widely distributed worldwide, except in most areas of Asia where Japanese encephalitis virus (JEV) is distributed. Considering the movement and migration of reservoir birds, there is concern that WNV may be introduced in Asian countries. Although manuals and guidelines for serological tests have been created in Japan in preparedness for the introduction of WNV, differential diagnosis between WNV and JEV may be complicated by antigenic cross-reactivities between these flaviviruses. Here, we generated a monoclonal antibody specific for the nonstructural protein 1 (NS1) of WNV and established an epitopeblocking enzyme-linked immunosorbent assay that can differentiate WNV from JEV infections in horse sera. Under conditions well suited for our assay system, samples collected from 95 horses in Japan (regarded as negative for WNV antibodies), including those collected from horses naturally infected with JEV, showed a mean inhibition value of 8.2% and a standard deviation (SD) of 6.5%. However, inhibition values obtained with serum used as a positive control (obtained after 28 days from a horse experimentally infected with WNV) in nine separate experiments showed a mean of 54.4% and an SD of 7.1%. We tentatively determined 27.6% (mean _3 _SD obtained with 95 negative samples) as the cutoff value to differentiate positive from negative samples. Under this criterion, two horses experimentally infected with WNV were diagnosed as positive at 12 and 14 days, respectively, after infection. 301 Leblond, A, Hendrikx P, Sabatier P. West Nile virus outbreak detection using syndromic monitoring in horses. Vector Borne Zoonotic Dis. 2007;7(3):403-10. Abstract Recent outbreaks of West Nile virus–associated (WNV) diseases, both in the old World and Americas, underline the importance for early warning systems that rapidly identify emerging and re-emerging diseases and thus help in their control. Traditional approaches of disease monitoring become less reliable and increasingly costly when used for rare health-related events, such as WNV outbreaks in southern France. The objective of this work was to discuss methodological issues related to syndromic monitoring of WNV- associated disease in Camargue horses by veterinary practitioners. Tracking cases of equine encephalitis by veterinarians is an example of such syndromic monitoring of an emerging disease. Signs of illness, observed prior diagnostic confirmation, can be of interest because they may provide an early warning for WNV circulation in a given area and allow authorities to take appropriate preventive measures for public health. Key Words: Monitoring—Epizootic—Syndrome—West Nile virus—Veterinary practitioners—Horses. 302 Long, MT,et.al. (2007) Efficacy, duration, and onset of immunogenicity of a West Nile virus vaccine, live Flavivirus chimera, in horses with a clinical disease challenge model. Equine Vet J.;39(6):491-7 Abstract Reasons for performing study: West Nile virus (WNF) is a Flavivirus responsible for a life-threatening neurological disease in man and horses. Development of improved vaccines against Flavivirus infections is therefore important. Objectives: To establish that a single immunogenicity dose of live Flavivirus chimera (WN-FV) vaccine protects horses from the disease and it induces a protective immune response, and to determine the duration of the protective immunity. Methods: Clinical signs were compared between vaccinated (VACC) and control (CTRL) horses after an intrathecal WNV challenge given at 10 or 28 days, or 12 months post vaccination. Results: Challenge of horses in the immunogenicity study at Day 28 post vaccination resulted in severe clinical signs of WNV infection in 10/10 control (CTRL) compared to 1/20 vaccinated (VACC) horses (P<0.01). None of the VACC horses developed viraemia and minimal histopathology was noted. Duration of immunity (DPI) was established at 12 months post vaccination. Eight of 10 CTRL exhibited severe clinical signs of infection compared to 1 of 9 VACC horses (P<0.05). There was a significant reduction in the occurrence of viraemia and histopathology lesion in VACC horses relative to CTRL horses. Horses challenged at Day 10 post vaccination experienced moderate or severe clinical signs of WNV infection in 3/3 CTRL compared to 5/6 VACC horses (P<0.05). Conclusions: This novel WN-FV chimera vaccine generates a protective immune response to WNV infection in horses that is demonstrated 10 days after a single vaccination and lasts for up to one year. Potential relevance: This is the first USDA licensed equine WNV vaccine to utilise a severe challenge model that produces the same WNV disease observed under field conditions to obtain a label claim for prevention of viraemia and aid in the prevention of WNV disease and encephalitis with a duration of immunity of 12 months 303 Long, MT, et.al. (2007) Safety of an attenuated West Nile virus vaccine, live Flavivirus chimera in horses. Equine Vet J.; 39(6): 486-90. Abstract Reasons for performing study: West Nile virus (WNV) infection is endemic and able to cause disease in naïve hosts. It is necessary therefore to evaluate the safety of new vaccines. Objectives: To establish: 1) the safety of a modified live Flavivirus/West Nile virus (WN-FV) chimera by administration of an overdose and testing for shed of vaccine virus and spread to uninoculated sentinel horses; 2) that this vaccine did not become pathogenic once passaged in horses; and 3) vaccine safety under field conditions. Methods: There were 3 protocols: 1) In the overdose/shed and spread study, horses were vaccinated with a 100x immunogenicity overdose of WN-FV chimera vaccine and housed with sentinel horses. 2) A reversion to virulence study, where horses were vaccinated with a 20x immunogenicity overdose of WN-FV chimera vaccine. Horses in both studies were evaluated for abnormal health conditions and samples obtained to detect virus, seroconversion and dissemination into tissues. 3) In a field safety test 919 healthy horses of various ages, breeds and sex were used. Results: Vaccination did not result in site or systemic reactions in either experimental or field- injected horses. There was no shed of vaccine virus, no detection of vaccine virus into tissue and no reversion to virulence with passage. Conclusions: WN-FV chimera vaccine is safe to use in horses with no evidence of ill effects from very high doses of vaccine. There was no evidence of reversion to virulence. In addition, administration of this vaccine to several hundred horses that may have been previously exposed to WNV or WNV vaccine resulted in no untoward reactions. Potential relevance: These studies establish that this live attenuated Flavivirus chimera is safe to use for immunoprophylaxis against WNV disease in horses 304 Seino, K.K,et.al. (2007) Comparative efficacies of three commercially available vaccines against West Nile Virus (WNV) in a short-duration challenge trial involving an equine WNV encephalitis model. Clin Vaccine Immunol.;14(11):1465-71. Abstract We used a severe challenge model that produces clinical West Nile virus (WNV) disease to test the efficacy of three commercially available equine WNV vaccines in horses. Twenty-four healthy, WNV-seronegative horses of varying ages and genders were placed, in random and blind manner, into three trial groups consisting of eight horses each; two horses in each group received (i) an inactivated WNV vaccine (K-WN), (ii) a modifiedlive vaccine (CP-WN) containing the WNV prM and E proteins expressed by a canarypox vector, (iii) a live-chimera vaccine (WN-FV) containing WNV prM and E proteins expressed in a YF17D vector, or (iv) a diluent control. Challenge by this model caused grave neurological signs, viremia, moderate to severe histopathologic lesions in the brain and spinal cord, and an outcome of 0% survivorship in all six control horses. In contrast, challenge in horses at between 28 days postvaccination with the chimera vaccine and 56 days postvaccination with the commercial inactivated or modified-live vaccine resulted in 100% survivorship (protection from the onset of WNV encephalitis and viremia). Horses vaccinated with the live-chimera vaccine showed significantly fewer clinical signs than did the control horses (P < 0.01) and the horses vaccinated with inactivated vaccine (P - 0.035). Mild residual inflammatory lesions were seen in a few of the vaccinated horses. 305 Nollet, H. and P. Deprez (2005) Hereditary skeletal muscle diseases in the horse.A review. Veterinary Quarterly, 27:2, 65-75, Abstract Since riders nowadays are expecting the highest level of performance from their horses, muscular disorders therefore represent a major problem for the equine athlete. A lot of research has been done to identify muscular disorders and their etiopathogenesis. Both acquired and inherited forms of muscle diseases have been described. In this review only the latter forms will be mentioned. Major signs of all muscle disorders are muscular stiffness, cramping or pain, muscular fasciculations, muscular atrophy and exercise intolerance. Muscle biopsies can help to identify the cause of rhabdomyolysis or muscular atrophy. However, especially in hereditary muscular diseases, a lot of questions are still to be answered. Increasing knowledge of the etiopatho- genesis and newer diagnostic tests may lead to a more accurate diagnosis of the individual diseases in future 306 Yuriadi (2003) Resistensi dan sensitivitas bakteri pada kuda penderita Pneumonia di Wil. DIY.- Jurnal Sain Veteriner, 21: 6-13 Abstract Telah dilakukan penelitian resistensi dan sensitivitas bakteri pada kuda penderita Pneumonia di Wilayah Daerah Istimewa Yogyakarta. Penelitian ini menggunakan 20 ekor kuda yang menderita Pneumonia, sampel diambil dari batang trakea kuda dengan cara memasang sonde dimasukkan ke dalam tabung steril dan dikirim ke laboratorium Balai Laboratorium Kesehatan. Dinas kesehatan dan kesejahteraan sosial, Propinsi DIY. Dari 20 buah swab sampel diperoleh 29 isolat bakteri, terdiri dari 8 macam yaitu Streptococcus spp. 7 isolat (24%), Klebsiella sp. 6 isolat (21%). Stapylococcus spp. 5 isolat (17%), dan Salmonella sp. 1 isolat (3%). Dari 29 isolat terdiri dari 8 macam bakteri yang setelah dilakukan uji resistensi dan sensitivitas bakteri dengan antibiotika penisilin, streptomisisn, ampisilin, tertrasiklin, dan sulfametaksasol berturut-turut hasilnya adalah penisilin resisten 90% dan sensitif 62%, tetrasiklin 10% dan sensitif 90%, sulfametaksasol resisten 7% dan sensitif 93%. Bakteri yang terisolasi dari batang trakea terdiri dari bakteri Gram positif dan Gram negatif.