Status of synthetic pyrethroid susceptibility/resistance in Rhipicephalus (Boophilus) microplus ticks of South India using allele-specific polymerase chain reaction

Rhipicephalus (Boophilus) microplus ticks with a previous history of acaricidal treatment with synthetic pyrethroids (SP) such as cypermethrin, deltamethrin and flumethrin were randomly collected from cattle of different pockets of southern states of India namely Tamil Nadu, Kerala, Karnataka, Andhra Pradesh and Puducherry from cattle. DNA extracted from pooled adult R. microplus ticks from each state was subjected to allele specific polymerase chain reaction (AS–PCR) to detect point mutation in sodium channel gene and a second AS– PCR was standardized to detect single nucleotide polymorphism in carboxyl esterase gene of R. microplus ticks. Mutation could not be detected either in sodium channel or carboxylesterase gene of R. microplus indicate that these ticks are susceptible to SP.