Abstract
To understand the benzimidazole (BZ) resistance of Haemonchus contortus in Southern Xinjiang, three single nucleotide polymorphisms (SNPs, designated F167Y, E198A and F200Y) in the isotype-Ⅰβ-tubulin gene which are associated with BZ resistance were investigated for H. contortus populations from sheep in some areas of Southern Xinjiang༎In brief, a total of 190 H. contortus adults were collected from 52 out of 70 slaughtered sheep in city abattoirs across two regions in Southern Xinjiang, and species identity of each adult worm was confirmed by PCR amplification of ITS-2 using H. contortus-specific primers targeting the ITS-2. The samples were then investigated by PCR-sequencing of the isotypeⅠβ-tubulin gene for analyzing BZ-related SNPs at locus 167, 198 and 200༎The results showed that only E198A and F200Y mutations were detected in the investigated H. contortus populations. E198A mutation (homozygous and heterozygote resistant: found in 40% and 30% of sequenced samples from Minfeng and Hejing county, respectively) was predominant compared with F200Y (homozygous and heterozygote resistant: found in 14% and 13.33% of sequenced samples from Minfeng and Hejing county, respectively). The results indicate a high prevalence of BZ resistance in H. contortus populations from certain areas of Southern Xinjiang. Our findings provide valuable information for the prevention and control of H༎contortus in areas with similar condition༎