Contagious Equine Metritis - Foreign Animal Disease Spotlight Volume 1 Issue 4 Winter 2006

Foreign Animal Disease Surveillance Newsletter

Figure. Distribution of participating veterinary clinics (purple Xs) and the 13 herd sampling locations (red Xs) in 10 of the 15 ecological zones of Texas. Interpolated proportion is the proportion of non-specific FMD PCR reactions expected across the different regions of Texas. Texas is free of FMD

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Contagious Equine Metritis - Foreign Animal Disease Spotlight Volume 1 Issue 4 Winter 2006

Research Update expected proportion of non-specific PCR reactions based on a statistical model and Welcome to the fourth installment of the preliminary results. Data are still being Foreign Animal Disease Surveillance analyzed here at TAMU and at FADDL, Newsletter. We are continuing to collect however, results to date indicate that suspect samples from market cattle and individual reactions are more likely in east Texas and sick cattle. We appreciate your help with the north panhandle region. We hypothesize this study and keep those sick cattle that there are organisms in the environment submissions coming. Also, please of cattle that cause these reactions and their remember to send an invoice with the serum distribution will be helpful for the design of sample from these animals otherwise we future surveillance programs. will not be able to process the $20 payment. The herd sampling and FMD testing was The map on the front page of the newsletter performed based on the 15 ecological zones shows results from another aspect of our according to the Texas Agriculture research program being performed in Statistical Districts. The number of cattle conjunction with Dr. Garry Adams (TAMU within each zone was obtained from 2002 CVM Department of Pathobiology) and Texas county-level estimates. The sample scientists at the Foreign Animal Disease size per ecological zone was selected Diagnostic Laboratory (FADDL) located on proportional to the total number of cattle in Plum Island, NY. The 1088 cattle sampled the zone. Texas Agricultural Experiment from 13 locations in Texas were tested for Research & Extension Centers (TAEREC) Foot-and-Mouth Disease Virus (FMDV) were identified in each ecological zone and using a real-time reverse-transcriptase PCR cattle at these locations were selected for developed at FADDL. Texas does not have sampling. Private herds were enrolled for FMD and these cattle were tested to estimate regions in which a TAEREC was not how many false-positive test results would present. be expected from different locations. The Geoff Fosgate [email protected] shading on the graph demonstrates the Michael Ward [email protected] Bo Norby [email protected]

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Contagious Equine Metritis - Foreign Animal Disease Spotlight Volume 1 Issue 4 Winter 2006

Contagious Equine Metritis 2006, CEM was confirmed in two Lipizzaner stallions. They were imported

Etiology from Eastern Europe and maintained in Contagious equine metritis (CEM) is a Dane county Wisconsin at an equine venereal disease of horses caused by the breeding and research facility. The stallions microaerophilic gram-negative cocobacillus underwent a breeding soundness exam and bacterium, equigenitalis. Two were found to be positive for CEM by strains of the bacterium can be recognized laboratory diagnostics (pathogen isolation one being resistant and the other susceptible on cell culture) performed at the National to . Infection with Taylorella Veterinary Services Laboratories. equigenitalis can cause metritis leading to infertility and in rare instances, abortion. Transmission

CEM is highly contagious and is considered T. equigenitalis is most frequently a foreign animal disease in the U.S. It is transmitted during mating. It can also be known to be present in many European spread indirectly through artificial countries and Japan. CEM was first insemination and the use of contaminated identified in England in 1977, but was most instruments and equipment. Undetected likely already endemic in other countries at carrier mares and stallions are a source of the time of first recognition. The first case infection to other horses. in the U.S. was diagnosed in 1978 on a Thoroughbred farm in Kentucky. The Hosts source of the outbreak was traced to the Equine species are the only known hosts for importation of 2 stallions from France in late T. equigenitalis. Donkeys can be affected 1977. Missouri had a subsequent outbreak under experimental conditions but naturally in 1979. The disease was eliminated from acquired infection has not been documented. both states and was not recognized again in the U.S. until a brief episode of cases in Clinical Signs California, Maryland, and Kentucky appeared in 1998. Recently, on October 4th Twenty-four hours after exposure to and

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Contagious Equine Metritis - Foreign Animal Disease Spotlight Volume 1 Issue 4 Winter 2006

colonization by T. equigenitalis and considered at risk for CEM should be inflammation develops and peaks after 10 tested to rule out infection because it is often days to 2 weeks. Clinical signs in mares difficult to distinguish this disease from become apparent 10 to 14 days after being other etiologies. In particular, infections exposed through natural cover or artificial with Klebsiella and Pseudomonas spp. of insemination. Stallions are not affected the reproductive tract can present with clinically and T. equigenitalis can persist on similar clinical signs. Proper authorities their external genitalia for years. Infection should be contacted before submitting of mares might be clinically unapparent or samples when CEM or any foreign animal they might show varying severity of signs disease is suspected. A sample should be that include metritis, mucopurulent vaginal sent in an approved secure container and the discharge, shortened estrous cycles, and authorized laboratory notified of its infertility. Infected mares might conceive shipment. The USDA Area Veterinarian in and either abort the fetus or give birth to an Charge for Texas should be contacted at infected carrier foal. Infection in mares can (512) 383-2400 or the Texas Animal Health result in acute or chronic disease or Commission at (512) 719-0700 to report the development of a silent carrier state. Acute possibility of a foreign animal disease. The disease results from an active inflammation samples should be submitted to the National of the uterus 10 to 14 days post mating. Veterinary Services Laboratories (NVSL) in Profound inflammation of the uterus results Ames, IA (803-788-1919) or to a laboratory in a thick mucopurulent vulvar discharge. approved by the Animal and Plant Health Chronic disease presents as milder uterine Inspection Service (APHIS). In mares, inflammation and less discharge. In the biopsy of the endometrium and swabs of the carrier state, can persist in the vaginal discharge, clitoral fossa, and clitoral reproductive tract from months to years. sinus should be sent for diagnostic testing. In the stallion, the urethra, urethral fossa and Diagnosis penile sheath should be swabbed and a sample of pre-ejaculatory fluid collected for Mares exhibiting signs of purulent metritis testing. Samples should be submitted to the

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Contagious Equine Metritis - Foreign Animal Disease Spotlight Volume 1 Issue 4 Winter 2006

laboratory in a transport medium that can be applied externally. Treatment can contains activated charcoal such as Amies require several months before the animal has medium, which supports growth of T. cleared the bacteria from internal and equigenitalis. The samples should be sent external locations. Chronic disease often chilled but not frozen within 48 hours of does not respond to therapy. collection. Serological testing can be used in mares suspected of being infected, but Prevention and Control bacterial culture is necessary for Equine entering the U.S. from endemic confirmation. Serologic testing is not countries are required to be quarantined for helpful in stallions because they do not a minimum of produce detectable antibodies against T. 3 days at a equigenitalis. USDA-

operated Treatment and Vaccination quarantine Contagious equine metritis can be treated facility and with oral in combination with tested for CEM along with other important external cleanings and topical foreign animal diseases. The USDA- therapy. Antibiotic selection should be operated quarantine facilities are located in based on in vitro sensitivity testing against New York, Los Angeles, and Miami. the isolated strain of T. equigenitalis. Additional health requirements may need to Cefotaxime, , , be met in accordance with specific state neomycin, and tetracycline have proven regulations. Since 2003 Texas no longer effectiveness for the treatment of T. accepts horses from regions affected with equigenitalis infetions. The external CEM. Animals that test positive should genitalia of the mare and stallion should be remain quarantined and treated until the washed with 2% chlorohexidine in a mild infection is resolved and no evidence of detergent and rinsed thoroughly. A topical chronic infection exists. Mares that are bred antibiotic such as a ointment to a stallion from another country should

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Contagious Equine Metritis - Foreign Animal Disease Spotlight Volume 1 Issue 4 Winter 2006

also be tested for CEM after breeding or http://www.vet.uga.edu/vpp/gray_book/FAD/ce artificial insemination. Horses that have m.htm tested positive for CEM should not be bred until they are proven to be free of T. http://www.animalhealthaustralia.com.au/shado mx/apps/fms/fmsdownload.cfm?file_uuid=2B24 equigenitalis infection. Instruments and 845D-FF8E-D5DE-2A0E- equipment should be properly cleaned and 9C498CD295B9&siteName=aahc. disinfected before and after use. Personnel should maintain appropriate hygiene when http://www.aphis.usda.gov/vs handling horses for breeding. This includes changing gloves between horses and http://mt.gov/liv/animalhealth/diseases/cem/ thoroughly cleaning their instruments and general.asp themselves.

http://www.cfsph.iastate.edu/ Public Health Significance

Contagious equine metritis is not known to http://www.oie.int affect humans and therefore does not pose a public health risk. http://equinereproduction.com/mareservices.

htm References http://www.vet.uga.edu/vpp/IVM/ENG/Age Bryans, J.T. and Hendricks J.B., 1978, ncies/intro4.htm Epidemiological observations on contagious equine metritis in Kentucky. J. Reprod. Fert.,

Suppl. 27, 343-349.

Swerczek, T.W., 1979, Contagious equine metritis-outbreak of the disease in Kentucky and laboratory methods for diagnosing the disease. J. Reprod. Fert., Suppl. 27, 361-365.

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