title: Benzimidazole resistance in Haemonchus contortus recovered from farmed red deer.
abstract: Thirty Haemonchus contortus male worms were collected from farmed red deer yearlings in order to determine whether routine administration of albendazole for a long-term period (17 years) could select anthelmintic resistance. PCR-RFLP method based on single-nucleotide polymorphism of codon 200 in isotype 1 ß-tubulin gene (Phe200Tyr) was applied. The results showed a significant frequency of either the resistant allele (85 %) or the homozygous resistant genotype (70 %). By chi-square test, Hardy-Weinberg equilibrium of the population was accepted (p = 0.334, power of test 0.01). True prevalence of the resistant genotype (RR) was estimated to be 46.5-87.2 % (confidence interval 95 %) calculated by Sterne's exact method. These results confirmed that long-term use of benzimidazoles could change the relative allele frequency of genes associated with drug resistance and may cause a large-scale spread of the resistant allele. To our knowledge, this study supported benzimidazole resistance in Haemonchus contortus in red deer for the first time.
authors.affiliation: Department of Animal Nutrition, Kaposvar University, H-7400, Kaposvár, P.O. Box 16, Hungary. nagy.gabor@ke.hu.
authors.forename: Gábor
authors.initials: G
authors.lastname: Nagy
authors.affiliation: Institute of Diagnostic Imaging and Radiation Oncology, Kaposvar University, H-7400, P.O. Box 16, Kaposvár, Hungary.
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Csivincsik
authors.affiliation: Department of Physiology and Animal Hygiene, Kaposvar University, H-7400, P.O. Box 16, Kaposvár, Hungary.
authors.forename: Attila
authors.initials: A
authors.lastname: Zsolnai
authors.affiliation: Department of Wildlife Biology and Ethology, Kaposvar University, H-7400, P.O. Box 16, Kaposvár, Hungary.
authors.forename: László
authors.initials: L
authors.lastname: Sugár
mesh_terms: D000383:Agriculture; D015766:Albendazole / Q000494:pharmacology*; D000483:Alleles; D000818:Animals; D000871:Anthelmintics / Q000494:pharmacology*; D003670:Deer / Q000469:parasitology*; D004351:Drug Resistance / Q000187:drug effects; D005838:Genotype; D006189:Haemonchus / Q000187:drug effects* / Q000302:isolation & purification; D008297:Male; D016133:Polymerase Chain Reaction / Q000379:methods; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D014404:Tubulin / Q000235:genetics
chemical_list: D000871:Anthelmintics; D014404:Tubulin; D015766:Albendazole
keywords: Albendazole; Haemonchus contortus; Red deer; Resistance