Evaluation of the efficacy of benzimidazoles against Ancylostoma caninum by egg hatch assay

Abstract

Monitoring of drug susceptibility or resistance is important to maintain the efficacy of currently available therapeutic agents against parasites of veterinary importance. The egg hatch assay was performed to determine the in vitro efficacy of thiabendazole against Ancylostoma caninum eggs collected from naturally infected dogs in Krishna district, Andhra Pradesh. The results revealed a highly significant (P<0.01) inhibitory effect on egg hatching rates by thiabendazole in a dose dependant manner. Thiabendazole resulted in 100% inhibition of egg hatching at a concentration of 0.048 μg/mL. Further, the effective doses (ED50) required to induce 50% inhibition of egg hatching was 0.0049 μg/ mL, which is lower than the discriminating dose of thiabendazole (0.1 μg/mL). The results revealed that A. caninum in the study area were susceptible to thiabendazole indicating benzimidazole resistance was absent or insignificant in the study area.