Real-time PCR assays for monitoring benzimidazole resistance-associated mutations in Ancylostoma caninum.

Frequent and broad application of anthelmintic drugs for treatment of intestinal parasite infection has led to drug resistance that often renders whole populations of livestock unresponsive to treatment. Therefore, it is important to detect mutations associated with drug resistance before it becomes clinically manifest. To monitor developing drug resistance against benzimidazoles (BZ), we developed real-time PCR assays and applied them to analyse the beta-tubulin isotype-1 gene of the hookworm Ancylostoma caninum, an important parasite of dogs. Previously, we developed PCR assays to monitor codon positions 167 and 200. Here, we describe an assay which is able to detect resistance alleles in codon 198. These real-time PCR assays were subsequently applied to screen hookworm specimens recovered from dogs in Georgia. No elevated levels of polymorphisms at the investigated loci were found, suggesting that selection for resistance in the tested samples did not occur.