Abstract: Background: Three single nucleotide polymorphisms (SNP) in the highly conserved beta-tubulin gene confer Benzimidazole resistance in many nematode parasites of veterinary and human importance. The F167Y SNP is associated with Ancylostoma caninum benzimidazole resistance in Greyhounds and other dog breeds.
Objective: A F167Y allele-specific real-time PCR (qPCR) was adopted and validated to screen hookworm positive samples.
Animals: Ninety-two fecal samples that tested positive for Ancylostoma by routine ova and parasite (O&P) and confirmed by Ancylostoma qPCR were included and screened for the presence of the 167Y resistance marker.
Methods: The Ancylostoma O&P positive fecal samples were verified by Ancylostoma specific qPCR. The 167Y resistance allele-specific qPCR was used to determine the frequency of Benzimidazole resistance genetic marker.
Results: The 167Y allele resistance marker was detected in 25 of the 87 (28.7%) Ancylostoma O&P and qPCR positive samples. Resistant allele positive samples were confirmed by beta-tubulin gene sequencing using flanking primers. No breed information was available from 10 samples; two samples were from a mixed breed and German Shepherd Dog, respectively. One sample was represented by each of the following breeds: Boxer, Golden doodle, Yorkshire terrier, Labrador retriever, Basenji, Siberian husky, American Staffordshire terrier, Beagle, Australia cattle dog, poodle and dachshund, respectively.
Conclusions and clinical importance: Anthelmintic resistance in hookworms is an emerging concern in veterinary medicine. Routine identification of the benzimidazole resistance genetic marker for Ancylostoma positive samples will aid in monitoring the prevalence of hookworm resistance and provide veterinarians with information that guides appropriate treatment decisions.