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Kocatepe Veterinary Journal

Kocatepe Vet J (2018) 11(3): 322-330 REVIEW DOI: 10.30607/kvj.429795

Submittion: 01.06.2018 Accepted: 08.07.2018 Published Online: 16.07.2018

Anthelmintic Resistance in Farm Animals

Mahmut Sinan EREZ1*, Esma KOZAN1

1Department of Parasitology, Faculty of Veterinary Medicine, Afyon Kocatepe University, Afyonkarahisar/TURKEY

*Corresponding author e-mail: [email protected]

ABSTRACT resistance means that developing genetically transmitted lack of susceptibility to an anthelmintic which is previously known to be susceptible to a parasite population. Anthelmintic resistance has an increasing importance in recent years. The anthelmintic resistance which is developed especially due to use of unconscious also brings with it economic problems. Investigations have shown that resistance has developed to anthelmintics in a short period of time after launch to the market and even in some countries, several sheep and goat farms have been closed due to anthelmintic resistance. For this reason, especially in livestock breeding; The development of resistance should not be overlooked while planning of treatment and control programs and choosing anthelmintics. In this review, resistance mechanisms which is developed to anthelmentic , resistance detection methods and anthelmentic resistance status of livestock in Turkey were evaluated.

Key words: Anthelmintics, Cattle, Goat, Resistance, Sheep

Çiftlik Hayvanlarında Antelmentik Direnç

ÖZ Bir parazit populasyonunun daha önce duyarlı olduğu bir antelmentiğe karşı gelişen ve genetik yolla aktarılan duyarlılık kaybı olarak değerlendirilen antelmentik direnç, son yıllarda giderek artan bir öneme sahiptir. Özellikle bilinçsiz ilaç kullanımına bağlı olarak gelişen antelmentik direnç ekonomik problemleri de beraberinde getirmektedir. Yapılan araştırmalar bazı ilaçların piyasaya sürümünü takiben kısa süreler içinde ilaca karşı bir direnç geliştiğini hatta bazı ülkelerde sadece direnç gelişmine bağlı olarak çiftliklerin kapatıldığı göstermektedir. Bu nedenle özellikle çiftlik hayvanları yetişrtiriciliğinde; antelmentik kullanılırken veya helmint enfeksiyonlarının tedavi ve kontrol programları planlanırken direnç gelişimi göz ardı edilmemeilidir. Bu derlemede antelmentik ilaçlara gelişen direnç mekanizmaları ve direnç tespit yöntemleri ile Türkiye’de çiftlik hayvanlarında belirlenen antelmentik direnç hakkında özlü bilgi verilmiştir.

Anahtar kelimeler: Antelmentikler, Direnç, Keçi, Koyun, Sığır

To cite this article: Erez M. S. Kozan E. Anthelmintic Resistance in Farm Animals. Kocatepe Vet J. (2018) 11(3):322-330.

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INTRODUCTION Genetic And Biological Factors Contributing Anthelmintic Resistance which is caused by parasites limit the Resistance is the heritable ability of the to welfare and yield of livestock around the world. survive a dose of anthelmintic which would The control of helminth infections is mostly based normally be effective. The resistance is inherited on the use of anthelmintic drugs (McKellar and and passed to the next generation. If a Jackson, 2004). Anthelmintic resistance has resistance develops to one anthelmintic in a class, developed in a short period of time after drug other drugs in the same class will be effected and it launched to the market, as a result of the intense is called as side resistance. If a drug resistance and unconscious use of drugs. World Association develops to two or more different anthelmintic for the Advancement of Veterinary Parasitology groups, it is described as a cross or multiple (WAAVP) published methods to detect resistance. Several sheep and goat farms have been anthelmintic resistance to draw attention to this closed cause of in issue in 1992 (Coles et al. 1992). Anthelmintic Australia, South Africa and New Zealand (Kaplan resistance has become a serious problem, especially 2004, Geary 2005, Abbott et al. 2012). in sheep nowadays. In some countries such as Australia, United Kingdom, New Zealand and Although the development of anthelmintic South Africa, some sheep and goat farms have resistance seems to be slow at the beginning, the been closed due to multiple drug resistance resistance, it is increasingly continued after each (Kaplan 2004, Geary 2005). treatment and the susceptibility is eventually lost. Once resistance has developed in the parasite Anthelmintics population, it is not possible to sensitize this Anthelmintics constitutes the cornerstone to population again until now (Sangster and Dobson, control helminth infections. Until recently, there 2002). were three main broad-spectrum anthelmintic groups in the market. These are It is thought that the parasite population carries a (BZs); imidazothiazole and tetrahydropyrimidines resistant allele even before the drug is administered (I/Ts) and macrocyclic lactones (MLs). They are (Wolstenholme et al. 2004). According to another also classified as white, yellow and clear drug hypothesis, it is thought that the resistance occurs groups. Monepantel which is a member of amino- as a result of spontaneous and repetitive mutations acetonitrile derivatives (AAD) was found about 30 (Skuce et al. 2010). If an individual carries two years later than and classified as the alleles or copies of a gene, it is called as fourth anthelmintic group. Finally, Derquantel homozygous. If it carries different alleles or copies which is from spiroindoles group was classified as a of a gene, it is called as heterozygous. Homozygous fifth anthelmintic group and launched to the parasites could be sensitive or resistant. Although market as a combination with . Fourth the genetics of resistance is not fully understood, group and fifth groups are shown with orange and participating in a single gene for resistance leads to purple respectively (Abbott et al. 2012). develop resistance faster. In case of resistance genes are dominant, resistance will be developed Use of Low Dose Anthelmintics faster compared to recessive genes. Moreover, To ensure that the treatment is fully effective, the some parasites have various biologic features such animals should be weighed and appropriate dose as direct (monoxen) development without an should be given by calculating. The use of low-dose intermediate host, short life cycle and high fertility drugs are caused to remain alive of more parasites rate, which accelerates the development of and accelerates the development of anthelmintic resistance in a parasite population (Sangster et al. resistance after treatment. Decreased bioavailability 1998, Coles 2005). of the drug is related to drug administration routes and the animal species. Especially irregular topical Detection of Anthelmintic Resistance (pour-on) applications are caused predisposition to Anthelmintic resistance means that developing the development of anthelmintic resistance. The genetically transmitted lack of susceptibility to a pharmacokinetics of the anthelmintics are also drug which is previously known to be susceptible effective with regards to the development of to a parasite population. Detection of anthelmintic resistance. As a result of using long-acting or slow resistance in a parasite population is very important releasing anthelmintics, the host is exposed to low when the frequency of alleles is low. Thus, doses at the end of the elimination phase. Thus, development of anthelmintic resistance could be short-acting anthelmintics are preferred delayed and susceptibility of the drug could be (Wolstenholme et al. 2004, Sutherland and preserved (Martin et al. 1989). Leathwick, 2011).

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Currently, the detection of anthelmintic resistance disadvantages of this method are being expensive, is based on in vivo and in vitro tests. Using of time-consuming and labor-intensive. Also, using these tests are limited because of taking a long animals for testing possess some ethical problems time, expensive, labor-intensive and required test (Coles et al. 1992, Taylor et al. 2002). animals. Some of the tests which are used to detect anthelmintic resistance are only successful if the In Vitro Methods for The Detection of target parasite population is 25% or more resistant Anthelmintic Resistance phenotypically (Coles et al. 1992). The advantages of in vitro tests are being low cost, not differ from host to host and not necessary to In Vivo Methods for The Detection of use testing animals. Many methods have been Anthelmintic Resistance developed to detect anthelmintic resistance using The two most commonly used methods for the larvae. The most of these tests are detecting anthelmintic resistance are; fecal egg not widely used practically because of reliability, count reduction test (FECRT) and the controlled reproducibility, sensitivity, and easy interpretation efficacy test (CET). Although the controlled- of tests are not at the desired level. Only Egg efficacy test is the most trustable method, the fecal Hatching Test (EHT) and Larval Developmental egg count reduction test is the most widely used Test (LDT) are widely used (De Graef 2013). In test as an in vivo method (De Graef 2013). addition, Larval Paralysis Test, Micro-Motility Measurement Test, Larval Migration Inhibition Fecal Egg Count Reduction Test (FECRT) Test and Molecular-Based Tests are used (Coles Fecal egg count reduction test is the most practical 2005, Jabbar et al. 2006, Demeler et al. 2010). in vivo method for detecting anthelmintic resistance and has been recommended by the Egg Hatching Test (EHT) World Association for the Advancement of The egg hatching test is only used to detect Veterinary Parasitology (WAAVP). This method is and resistance, but can based on the calculation of the difference as a not be used in macrocyclic lactones due to not percentage after counting of nematode eggs in being ovicidal. Eggs are incubated at various feces for pre-treatment and post-treatment (10-14 concentrations with anthelmintics to calculate the days later). It is considered to develop resistance if percentage of egg hatching after the eggs are the number of eggs per gram (EPG) in the stool obtained from the feces (Taylor et al. 2002, Coles decreases by a percentage below 95% after 2005). The optimal dose is calculated using treatment (Coles et al. 1992). sensitive isolates. In the tested samples, the percentage of egg hatching is also regarded as the This test is available for all the anthelmintics. If percentage of resistance. An advantage of this parasite population has more than 25% resistance, method is that only once stool collection is it can be said that this technique is reliable. Ideally, sufficient (Coles et al. 2006). The results of the egg ten animals which have higher than 150 EPG are hatching test are generally interpreted using values selected for each group (Coles et al. 2006). of ED50 (50% inhibition value) or ED99 (99% If there are less than 50 EPG in feces, the modified inhibition value). If the ED50 is used as the McMaster technique cannot be used and this threshold value, resistant parasites in the situation limits the use of the technique. In case population must be at least 25% to detect that, the number of eggs in the stool before benzimidazole resistance. The sensitivity of the test treatment is less than 150, it is recommended to was increased with the use of ED99 value, and it use a more sensitive method. Another disadvantage has become possible to detect resistant parasites of this method is the lack of species specificity with a low percentage in the population (Várady et (Coles et al. 2006, Levecke et al. 2009). al. 2007).

Controlled Efficacy Test (CET) Larval Developmental Test (LDT) The controlled efficacy test is seen as the best The larval development test was developed to method to determine the effect of the measure the potential of the anthelmintic drug with anthelmintics (Martin et al. 1989, Cook et al. 2006). regards to inhibiting egg development. In this test, the animals are experimentally infected Trichostrongylid type eggs are incubated with with known resistant and susceptible L3 and then tested anthelmintics in the medium containing treated with different concentrations of the Escherichia coli for 6-8 days in this method and then anthelmintic. After a certain period of time, the ratio of developed L3 is calculated. The use of parasites are collected from the abomasum. If the freshly collected eggs is the most important factor decrease in the number of parasites is less than for working efficiently of the test (Demeler et al. 90% or more than 1000 parasites remain alive after 2010). The larval development test is used to treatment, it is considered to be resistant. The determine the resistance of many anthelmintics 324 including macrocyclic lactones, although it is more from the egg to L3 in nature, the cysted larvae in labor-intensive and time-consuming than the egg the abomasal glands and the untreated parasites in hatching test. Larval growth test is more sensitive the host (Abbott et al. 2012). Reducing the than FECRT and egg hatching test (EHT); it is proportion of resistant parasites in the population able to detect up to 10% of parasites carrying and delaying the development of resistance by resistance in populations (Jabbar et al. 2006). increasing the proportion of susceptible parasites constitutes the principle of refugia. Short treatment Larval Migration Inhibition Test intervals reduce the reproduction of susceptible Motility and migration and tests are based on parasites, while also reduce the number of paralyzing muscles of the trichostrongylid unexposed parasites. In addition, some animals in by way of anthelmintics. The third stage the herd should not be treated to maintain the larvae are incubated with anthelmintic serial presence of sensitive parasites (Sangster and dilutions for twenty-four hours and then Dobson, 2002). transferred onto a mesh for another twenty-four hours. In spite of resistant L3s pass through the Mechanism of Anthelmintic Resistance mesh, sensitive L3s remains on the mesh. Then the Benzimidazole Resistance percentage of migrating larvae is calculated. In genetic studies on benzimidazole-resistant Migration inhibition is determined by the curve gastrointestinal nematodes, several specific changes resulting from different concentrations (Demeler et in the beta-tubulin-encoding sequence lead to point al. 2010). mutations, thus reducing drug susceptibility (Von Samson-Himmelstjerna et al. 2007, Dicker 2010). Molecular-Based Tests Genetic studies on Teladorsagia circumcincta, T. DNA-based tests have been developed to identify colubriformis, H. concortus and have genetic-based qualitative or quantitative changes shown that tyrosine (resistant, TAC) is encoded (differences in gene expression). Low instead of phenylalanine (sensitive, TTC) at codon benzimidazole resistance which can not be 200 in beta-tubulin isotype 1 gene (Phe200Tyr or detected by in vitro methods can be determined F200Y) which is caused point mutation (Kwa 1994, with the development of molecular-based tests. Von Samson-Himmelstjerna et al. 2007). The Molecular-based tests are more sensitive and faster second, less common, benzimidazole resistance than in vivo and in vitro tests, in spite of expensive mechanism is the phenylalanine-tyrosine (Phe-Tyr) equipment and materials. These tests allow polymorphism at codon 167 which is seen individual detection of parasites which is carrying especially in the nematodes of horses resistance genes in a population (Von Samson- (Wolstenholme et al. 2004, Hodgkinson et al. 2008, Himmelstjerna 2006). Theoretically, even if the Silvestre and Cabaret, 2002). Tyr (Tyrosine) was frequency of resistance is low in the population, required at codon 200 for benzimidazole resistance molecular-based tests can detect resistance alleles. in Haemonchus concortus; The homozygous Polymerase Chain Reaction (PCR) based tests phenylalanine-phenylalanine (Phe/Phe), the detect benzimidazole resistance by using of single heterozygous phenylalanine-tyrosine (Phe / Tyr) or nucleotide polymorphisms (SNPs). Subsequent to homozygous tyrosine-tyrosine (Tyr/Tyr) at codon PCR, DNA is separated on agar electrophoresis 167 can cause the parasite to become resistant in T. and the bands revealed. Then real-time PCR and circumcincta. Tyr (Tyrosine) is required at codon 200 pyrosequencing techniques began to be used. So for benzimidazole resistance in Haemonchus concortus. far, most of the molecular research has been The homozygous phenylalanine-phenylalanine (Phe conducted on benzimidazoles to detect / Phe) at codon 200 and the heterozygous anthelmintic resistance. The resistance mechanism phenylalanine-tyrosine (Phe/Tyr) or homozygous of other anthelmintics is not as well known as tyrosine-tyrosine (Tyr/Tyr) at codon 167 in benzimidazoles yet, but studies are still being T.circumcincta can cause the parasite to become continued (Kwa et al. 1994, Jabbar et al. 2006, Von resistant (Silvestre and Cabaret, 2002, Von Samson-Himmelstjerna 2006). Samson-Himmelstjerna et al. 2007). Resulting from point mutation at codon 198, alanine (Ala) is Refugia encoded instead of glutamic acid (Glu) as an Parasites are called refugia, which have not been alternative mechanism of benzimidazole resistance exposed to an anthelmintic drug in a parasite which is found in H. contortus (Ghisi et al. 2007). population. Refugia is the basis of the large Some of the studies have shown that P- majority of sustainable parasite control programs. glycoproteins are indirectly involved in Refugia constitute one of the sources of re- benzimidazole resistance of nematodes. Another and prevent resistant parasites from mechanism of resistance to benzimidazole is the becoming a majority of the population. Also, it deletion of β-tubulin isotype 2 in the H.concortus consists of developmental stages of the parasite population. While heterozygous parasites are 325 advantageous compared with susceptible parasites GABA-gated chloride channels (Gilleard, 2006). in terms of benzimidazole resistance, although it is Changes in allele frequencies of glutamate and not completely resistant. Parasites are more likely GABA chlorine subunits were observed in to survive, especially after inadequate dosing of different populations of , but anthelmintics (Roos et al. 1995, Von Samson- the changes in a single allele were not correlated Himmelstjerna 2006). with resistance (Blackhall et al. 1998, Blackhall et al. 2003). Macrocyclic lactone resistance is emerged by Levamisole Resistance mutation of a few glutamate-gated chloride subunit There are insufficient studies on the resistance genes in C. elegans (McCavera et al. 2007). In order mechanisms of tetrahydropyrimidines including to develop a high level of ivermectin resistance in levamisole, imidazothiazole and (Kopp et C. elegans, simultaneous mutation is required in all al. 2009). Studies on Caenorhabditis elegans have three genes (avr-14, avr-15 and glc-1) which is shown; 5 genes that encode the subunits (L- encoding α-subunit of the glutamate-gated chloride AChRs) of ionotropic acetylcholine receptors channel. Avr-15 encodes GluCla2 which is which is sensitive to levamisole resistance. These expressed in the pharyngeal muscles of C. elegans are 3 α-subunit genes (lev-8, unc-63, unc-38) and 2 and Avr-14 encodes GluCla3 which is expressed in non-α subunit genes (lev-1, unc 29) (Fleming et al. the extrapharyngeal nerve cell of C. elegans. One of 1997, Boulin et al. 2008 ). In addition, the L-AChR the most important mechanisms of action of expression is lost in muscle cells due to mutations ivermectin is the inhibition of the pharyngeal pump in ric-3, unc-74 and unc-50 and resulting in loss of which causes starvation of parasites (Dent et al. sensitivity to levamisole. For the development of 2000, Cook et al. 2006). While parasitic nematodes the levamisole resistance, glycine (Gly) must be have different GluCl subunit genes compared to C. encoded instead of glutamic acid (Glu) at codon elegans, there are also orthologs that reduce the 153 in the unc-38 gene of C. elegans (Rayes et al. sensitivity of ivermectin, such as avr-14 in C. 2004, Martin and Robertson, 2007). Lack of oncophora (McCavera et al. 2007). The genetic susceptibility to pyrantel receptors has occurred as mechanism of the ivermectin resistance in a result of encoding glycine (Gly) instead of Trichostrogylid parasites is not fully understood glutamine (Gln) at codon 57 of the unc-63 gene of (Geary 2005, Prichard and Roulet, 2007). C.elegans. (Bartos et al. 2006). Nicotinic acetylcholine receptors consist of 5 glycoprotein Changes in the γ-amino butyric acid (GABA) subunits which are arranged around a central ion receptor genes are thought to be responsible for channel and each subunit gains different the macrocyclic lactone resistance (Blackhall et al. pharmacological properties to the nAChR (Fleming 2003). et al. 1997). Expression difference in HA17, which is a gene fragment, between levamisole-sensitive Detoxification process of P-glycoproteins (PGP) is and levamisole resistant parasites was identified by thought to play a role in macrocyclic lactone cDNA-AFLP technique and aimed to be a resistance. P-glycoproteins are a member of the potential marker for detection of levamisole ATP binding cassette superfamily and provide resistance (Neveu et al. 2007). In Ancylostoma active transport of endogenous and exogenous caninum, significant polymorphic differences were hydrophobic molecules across the membrane not observed in ARR-29, ARR-38 and ARR-63, (Sangster and Dobson, 2002). P-glycoproteins are which are subunits of the pyrantel, but it was significantly localized in the digestive tract and it is proven that expression of these genes is expressed at high levels in the membranes of the significantly reduced in resistant parasites. These intestinal and pharyngeal cells (Smith and Prichard, genes are ortholog with the unc-29, unc-38 and unc- 2002). The main role of P-glycoproteins is to 69 genes which is found in C.elegans (Kopp et al. protect the organism by pumping toxic agents out 2009). of the cell. It has been reported that Tc-Pgp-9, which is a kind of PGP in the study on ivermectin Macrocyclic Lactone Resistance resistant T.circumcincta, has increased expression at The mechanism of macrocyclic lactone resistance mRNA level, high level of polymorphism in has not been fully understood yet. Glutamate-gated sequence, and helminths may play an important chloride channels and acetylcholine receptors have role in resistance to ivermectin. It has been a similar structure and the central ion channel are reported that increased expression at mRNA level constituted by the combination of 5 subunits (α and high level of polymorphism in the sequence and β). The α subunits contain the glutamate are observed in Tc-Pgp-9 which is obtained from binding site, while the β subunits contain the ivermectin resistant T. circumcincta of sheep and it ivermectin binding site (Martin et al. 1997, Bartos has been determined that it may play an important et al. 2006). Some of the genes which are involved role with regards to ivermectin resistance of in ivermectin resistance include glutamate and helminths. Pgp-inhibited mice and Collie dogs with 326

PGP deficiency are highly susceptible to ivermectin Alternative treatment methods have been studied and result in death as a result of extreme due to the problem of anthelmintic resistance in neurotoxicity (Lespine et al. 2008, Dicker et al. many regions of the world. The most common 2011). alternative treatment methods are; copper oxide wire particles, use of tannin-containing feeds, Verapamil, as a , inhibits nematode-trapping fungi, , breeding for the binding site of Pgp, thereby increasing the resistant animals, nutrition and using anthelmintic efficiency of the anthelmintics. In vitro using of activities of medical plants (Fleming et al. 2006, verapamil as a Pgp inhibitor has shown that Jabbar et al. 2006). macrocyclic lactone-resistant parasites become more sensitive (Demeler et al. 2013). Anthelmintic Resistance in Turkey Çırak et al. 2004 performed FECRT to detect the Amino-Acetonitrile Derivatives (AAD) resistance status of strongylid nematodes on ten Resistance horse farms in Western Anatolia. Seven farms were Monepantel was first used in small ruminants in found to be infected with the resistant 2009 with the commercial name Zolvix®, and the cyathostomin population to benzimidazoles. first resistance case was reported four years later Resistance of pyrantel embonate on five farms and after introduced to the market (Scott et al. 2013). macrocyclic lactone on six farms were investigated, Then there are different resistance reports from but anthelmintic resistance was not detected. various parts of the world (Mederos et al. 2014, Love 2014, Cintra et al. 2016). Tınar et al. 2005 tested anthelmintic resistance in trichostrongylid nematodes of small ruminants by Monepantel which is a member of amino- FECRT on twelve sheep and goat farms. acetonitrile derivatives targets nicotinic receptors as , , tetramisole and the mechanism of action. These receptors include ivermectin resistance were tested and tetramisole DES-2 and ACR-23 subunits which is located in resistance was detected in only one sheep farm. the pharyngeal muscles, between the nerves throughout nerve cord and the sensory nerves. Köse et al. 2007 tested albendazole, - Subunits of nicotinic acetylcholine receptors and ivermectin resistance by FECRT sensitive to amino-acetonitrile derivatives have a on seven sheep farms in Afyonkarahisar and found mechanism that only affects nematodes, and so it is that ivermectin did not work at the desired level in not toxic to mammals, insects and other five farms. vertebrates. In vitro studies on Haemonchus contortus have shown that two genes are effective on Çırak et al. 2010 found that macrocyclic lactone resistance. As a result of deletions at the intron- groups against in a horse farm exon border in monepantel-1 (Hco-mptl-1, also were resistance. called Hc-acr-23H) gene of resistant H. concortus, stop codon is located before the regular site. Önder et al. 2016 determined the frequency of Another mutation is occured by 5' end insertional benzimidazole-sensitive and resistant alleles in the mutation in the Hco-des-2H gene and result in H.concortus population by 87.1% and 12.9%, decreased susceptibility (Rufener et al. 2009, respectively, and revealed the BZ resistance by the Kennedy and Harnett, 2013). molecular method.

Famacha (Faffa Malan Chart) RESULTS Famacha is a low cost and easily applicable test which is developed by South African scientists to Consequently, as World Association for the determine the anemia associated with Advancement of Veterinary Parasitology haemonchosis in sheep and goats and it is aimed to (WAAVP) has also noted, anthelmintic resistance is avoid unnecessary use of anthelmintics. This test is a very important and restrictive factor especially in widely used in Sub-saharan Africa and South livestock breeding. For this reason, the America. The principle of this test is based on a development of resistance to anthelmintics should comparison of the color of the eye conjunctiva of not be overlooked in the selection and small ruminants with the Famacha card to implementation of treatment and control options determine the severity of the anemia (Malan et al. for helminth infections. 2001). REFERENCES Alternative Control Methods of Anthelmintic Resistance Abbott KA, Taylor MA, Stubbings LA. SCOPS– Sustainable Control Strategies for 327

Sheep 4th Edition: A Technical Manual for Veterinary parasitology, (2006); 136(3), 167- Veterinary Surgeons and Advisers. Context 185. Publishing, (2012). Bartos M, Rayes D, Coles GC. Anthelmintic resistance–looking to the Bouzat C. Molecular determinants of future: a UK perspective. Research in pyrantel selectivity in veterinary science, (2005); 78(2), 99-108. nicotinic receptors. Molecular , (2006); 70(4), 1307-1318. Cook A, Aptel N, Portillo V, Siney E, Sihota R, Holden-Dye L, Wolstenholme A. Blackhall WJ, Pouliot JF, Prichard RK, Beech Caenorhabditis elegans ivermectin receptors RN. Haemonchus contortus: selection at a regulate locomotor behaviour and are glutamate-gated chloride channel gene in functional orthologues of Haemonchus ivermectin-and -selected strains. contortus receptors. Molecular and Experimental parasitology, (1998); 90(1), 42- biochemical parasitology, (2006); 147(1), 48. 118-125. Blackhall WJ, Prichard RK, Beech RN. De Graef J. Detection and mechanisms of Selection at a γ-aminobutyric acid receptor macrocyclic lactone resistance in the bovine gene in Haemonchus contortus resistant to nematode Cooperia oncophora, (2013). /. Molecular and biochemical parasitology, (2003); 131(2), De Graef, J., Claerebout, E., & Geldhof, P. 137-145. (2013). Anthelmintic resistance of gastrointestinal cattle nematodes. Vlaams Boulin T, Gielen M, Richmond JE, Williams Diergeneeskundig Tijdschrift, 82(3), 113- DC, Paoletti P, Bessereau JL. Eight genes 123. are required for functional reconstitution of the Caenorhabditis elegans levamisole- Demeler J, Krücken J, Al Gusbi S, Ramünke S, sensitive acetylcholine receptor. Proceedings De Graef J, Kerboeuf D, Geldhof P, of the National Academy of Sciences, Pomroy WE, von Samson- (2008); 105(47), 18590-18595. Himmelstjerna G. Potential contribution of P-glycoproteins to macrocyclic lactone Cırak, VY, Kar S, Girişgin O. İvermektin ve resistance in the cattle parasitic nematode pirantele karşı at Strongylidae’lerinde Cooperia oncophora. Molecular and antelmentik direnç araştırılması ve Parascaris biochemical parasitology, (2013); 188(1), 10- equorum’da makrosiklik lakton direnci. 19. Türkiye Parasitol Derg, (2010); 34, 35-39. Demeler J, Küttler U, von Samson- Cintra MCR, Teixeira VN, Nascimento LV, Himmelstjerna G. Adaptation and Sotomaior CS. Lack of efficacy of evaluation of three different in vitro tests for monepantel against Trichostrongylus the detection of resistance to anthelmintics colubriformis in sheep in Brazil. Veterinary in gastro intestinal nematodes of cattle. parasitology, (2016); 216, 4-6. Veterinary parasitology, (2010); 170(1), 61- Cirak VY, Güleğen E, Bauer C. Benzimidazole 70. resistance in cyathostomin populations on Dent JA, Smith MM, Vassilatis DK, Avery L. horse farms in western Anatolia, Turkey. The genetics of ivermectin resistance in Parasitology Research, (2004); 93(5), 392- Caenorhabditis elegans. Proceedings of the 395. National Academy of Sciences, (2000); 97(6), Coles GC, Bauer C, Borgsteede FHM, Geerts 2674-2679. S, Klei TR, Taylor MA, Waller PJ. World Dicker AJ, Nisbet AJ, Skuce PJ. Gene Association for the Advancement of expression changes in a P-glycoprotein (Tci- Veterinary Parasitology (WAAVP) methods pgp-9) putatively associated with ivermectin for the detection of anthelmintic resistance resistance in Teladorsagia circumcincta. in nematodes of veterinary importance. International journal for parasitology, Veterinary parasitology, (1992); 44(1-2), 35- (2011); 41(9), 935-942. 44. Dicker AJ. Comparative gene expression studies Coles GC, Jackson F, Pomroy WE, Prichard of anthelmintic resistance in the parasitic RK, von Samson-Himmelstjerna G, nematode, Teladorsagia circumcincta Silvestre A, Taylor MA, Vercruysse J. The (Doctoral dissertation, University of detection of anthelmintic resistance in Glasgow), 2010. nematodes of veterinary importance.

328

Fleming JT, Squire MD, Barnes TM, Tornoe Western Turkey. Parasitology research, C, Matsuda K, Ahnn J, Fire A, Sulston (2007); 101(3), 563-567. JE, Barnard EA, Sattelle DB, Lewis JA. Kwa MS, Veenstra JG, Roos MH. (1997). Caenorhabditis elegans Levamisole Benzimidazole resistance in Haemonchus Resistance Geneslev-1, unc-29, and unc-38 contortus is correlated with a conserved Encode Functional Nicotinic Acetylcholine mutation at amino acid 200 in β-tubulin Receptor Subunits. Journal of Neuroscience, isotype 1. Molecular and biochemical 17(15), 5843-5857. parasitology, (1994); 63(2), 299-303. Fleming SA, Craig T, Kaplan RM, Miller JE, Lespine A, Alvinerie M, Vercruysse J, Prichard Navarre C, Rings M. Anthelmintic RK, Geldhof P. ABC transporter resistance of gastrointestinal parasites in modulation: a strategy to enhance the small ruminants. Journal of veterinary activity of macrocyclic lactone anthelmintics. internal medicine, (2006); 20(2), 435-444. Trends in parasitology, (2008); 24(7), 293- Geary TG. Ivermectin 20 years on: maturation of a 298. wonder drug. Trends in parasitology, (2005); Levecke B, De Wilde N, Vandenhoute E, 21(11), 530-532. Vercruysse J. Field validity and feasibility of Ghisi M, Kaminsky R, Mäser P. Phenotyping four techniques for the detection of and genotyping of Haemonchus contortus Trichuris in simians: a model for monitoring isolates reveals a new putative candidate drug efficacy in public health. PLoS mutation for benzimidazole resistance in neglected tropical diseases, (2009); 3(1), nematodes. Veterinary parasitology, (2007); e366. 144(3), 313-320. Love S. Monepantel (Zolvix®) resistance Gilleard JS. Understanding anthelmintic confirmed in goats in NSW Australia. resistance: the need for genomics and WormMail Newsletter, 6 June 2014. genetics. International journal for Malan FS, Van Wyk JA, Wessels CD. Clinical parasitology, (2006); 36(12), 1227-1239. evaluation of anaemia in sheep: early trials. Hodgkinson JE, Clark HJ, Kaplan RM, Lake The Onderstepoort journal of veterinary SL, Matthews JB. The role of research, (2001); 68(3), 165. polymorphisms at β tubulin isotype 1 Martin PJ, Anderson N, Jarrett RG. Detecting codons 167 and 200 in benzimidazole benzimidazole resistance with faecal egg resistance in cyathostomins. International count reduction tests and in vitro assays. journal for parasitology, (2008); 38(10), Australian Veterinary Journal, (1989); 66(8), 1149-1160. 236-240. Jabbar A, Iqbal Z, Kerboeuf D, Muhammad G, Martin RJ, Robertson AP, Bjorn H. Target sites Khan MN, Afaq M. Anthelmintic of anthelmintics. Parasitology, (1997); resistance: the state of play revisited. Life 114(7), 111-124. sciences, (2006); 79(26), 2413-2431. Martin RJ, Robertson AP. Mode of action of Kaplan RM. Drug resistance in nematodes of levamisole and pyrantel, anthelmintic veterinary importance: a status report. resistance, E153 and Q57. Parasitology, Trends in parasitology, (2004); 20(10), 477- (2007); 134(8), 1093-1104. 481. McCavera S, Walsh TK, Wolstenholme AJ. Kennedy MW, Harnett W. (Eds.). Parasitic Nematode ligand-gated chloride channels: nematodes: molecular biology, biochemistry an appraisal of their involvement in and immunology, (2013), CABI. macrocyclic lactone resistance and prospects Kopp SR, Coleman GT, Traub RJ, McCarthy for developing molecular markers. JS, Kotze AC. Acetylcholine receptor Parasitology, (2007); 134(8), 1111-1121. subunit genes from Ancylostoma caninum: McKellar QA and Jackson F. Veterinary altered transcription patterns associated with anthelmintics: old and new. Trends in pyrantel resistance. International journal for Parasitology, (2004); 20, (10), 456-461. parasitology, (2009); 39(4), 435-441. Mederos AE, Ramos Z, Banchero, GE. First Köse, M, Kozan E, Sevimli FK, Eser M. The report of monepantel Haemonchus resistance of nematode parasites in sheep contortus resistance on sheep farms in against anthelmintic drugs widely used in Uruguay. Parasites & vectors, (2014); 7(1), 598 329

Neveu C, Charvet C, Fauvin A, Cortet J, Skuce P, Stenhouse L, Jackson F, Hypša V, Castagnone-Sereno P, Cabaret J. Gilleard J. Benzimidazole resistance allele Identification of levamisole resistance haplotype diversity in United Kingdom markers in the parasitic nematode isolates of Teladorsagia circumcincta Haemonchus contortus using a cDNA- supports a hypothesis of multiple origins of AFLP approach. Parasitology, (2007); resistance by recurrent mutation. 134(8), 1105-1110. International journal for parasitology, (2010); 40(11), 1247-1255. Önder Z, Yildirim A, Inci A, Düzlü Ö, Çiloğlu A. Molecular Prevalence, Phylogenetic Smith JM and Prichard RK. (2002). Localization Characterization and Benzimidazole of p-glycoprotein mRNA in the tissues of Resistance of Haemonchus contortus from Haemonchus contortus adult worms and its Sheep. Kafkas Üniversitesi Veteriner relative abundance in drug-selected and Fakültesi Dergisi, 22(1), (2016); 93-99. susceptible strains. Journal of Parasitology, 88(3), 612-620. Prichard RK and Roulet A. ABC transporters and β-tubulin in macrocyclic lactone Sutherland IA, Leathwick DM. Anthelmintic resistance: prospects for marker resistance in nematode parasites of cattle: a development. Parasitology, (2007); 134(8), global issue. Trends in parasitology, (2011); 1123-1132. 27(4), 176-181. Rayes D, De Rosa MJ, Bartos M, Bouzat C. Taylor MA, Hunt KR, Goodyear KL. Molecular basis of the differential sensitivity Anthelmintic resistance detection methods. of nematode and mammalian muscle to the Veterinary Parasitology, (2002); 103(3), 183- anthelmintic agent levamisole. Journal of 194. Biological Chemistry, (2004); 279(35), Tinar, R, Akyol CV, Cirak VY, Şenlik B, Bauer 36372-36381. C. Investigations on the seasonal patterns of Roos MH, Kwa MSG, Grant WN. New genetic strongyle infections in grazing lambs, and and practical implications of selection for the occurrence of anthelmintic resistance on anthelmintic resistance in parasitic sheep and goat farms in western Anatolia, nematodes. Parasitology Today, (1995); Turkey. Parasitology research, (2005); 96(1), 11(4), 148-150. 18-23. Rufener L, Mäser P, Roditi I, Kaminsky R. Várady M, Čudeková P, Čorba J. In vitro Haemonchus contortus acetylcholine detection of benzimidazole resistance in receptors of the DEG-3 subfamily and their Haemonchus contortus: egg hatch test role in sensitivity to monepantel. PLoS versus larval development test. Veterinary pathogens, (2009); 5(4), e1000380. parasitology, (2007); (1), 104-110. Sangster NC and Dobson RJ. Anthelmintic Von Samson-Himmelstjerna G, Blackhall WJ, resistance. Taylor & Francis, (2002) McCarthy JS, Skuce PJ. Single nucleotide polymorphism (SNP) markers for Sangster NC, Redwin JM, Bjorn H. Inheritance benzimidazole resistance in veterinary of levamisole and benzimidazole resistance nematodes. Parasitology, (2007); 134 (8), in an isolate of Haemonchus contortus. 1077-1086. International journal for parasitology, (1998); 28(3), 503-510. Von Samson-Himmelstjerna G. Molecular diagnosis of anthelmintic resistance. Scott I, Pomroy WE, Kenyon PR, Smith G, Veterinary parasitology, (2006); 136(2), 99- Adlington B, Moss A. Lack of efficacy of 107. monepantel against Teladorsagia circumcincta and Trichostrongylus Wolstenholme AJ, Fairweather I, Prichard R, colubriformis. Veterinary parasitology, von Samson-Himmelstjerna, G, Sangster (2013); 198(1), 166-171. NC. Drug resistance in veterinary helminths. Trends in parasitology, (2004); Silvestre A and Cabaret J. Mutation in position 20(10), 469-476. 167 of isotype 1 β-tubulin gene of Trichostrongylid nematodes: role in benzimidazole resistance?. Molecular and biochemical parasitology, (2002); 120(2), 297-300.

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