The prevalence of E198A and F200Y single nucleotide polymorphism in Haemonchus contortus populations from Polish goat herds

A cross-sectional descriptive study was carried out on a study population of 81 goat herds to investigate the prevalence and frequency of two single nucleotide polymorphisms (SNPs; E198A and F200Y) associated with resistance to benzimidazoles (BZ) in Haemonchus contortus populations of goats in Poland. The distribution of gastrointestinal nematode (GIN) genera/species in a pooled fecal sample from each herd was determined in larval cultures and the presence of H. contortus DNA in larval cultures was confirmed using real-time PCR. SNPs were detected and their frequency was quantified using pyrosequencing. The Hardy–Weinberg principle was employed to estimate frequencies of H. contortus genotypes based on frequencies of alleles containing each SNP. At least one BZ resistance-associated SNP was detected in each within-herd (WH) H. contortus population—F200Y SNP in 79/81 WH H. contortus populations (98%) and E198A SNP in 80/81 WH H. contortus populations (99%). The median WH frequencies of F200Y and E198A were 86% and 8%, respectively. In the total Polish H. contortus population, the overall frequency of BZ-resistant genotypes was estimated at 89% (CI 95%: 82%–93%) and was positively and independently associated with the purchase of goats abroad (adjusted odds ratio [ORadj] 22.8 [CI 95%: 8.9–58.4]; p < 0.001), large size of herd (> 100 goats; ORadj 7.5 [CI 95%: 1.8–30.5]; p = 0.006), use of levamisole for goat deworming (ORadj 3.1 [CI 95%: 1.2–7.8]; p = 0.019), and multiple anthelmintic treatments per year (ORadj 3.1 [CI 95%: 1.0–9.5]; p = 0.046). The study shows that genetic resistance to BZ is widespread in H. contortus infecting Polish goats. Therefore, reconsideration of routine BZ use and implementation of integrated and sustainable parasite control strategies appears to be highly recommended.