Use of polymerase chain reaction: Restriction fragment length polymorphism to detect acaricidal resistance to synthetic pyrethroids in Boophilus microplus ticks of South India.

BACKGROUND: Boophilus microplus is an important ectoparasite of livestock. Apart from transmitting diseases, heavy tick burden can decrease production and damage hides. The synthetic pyrethroids which are advantageous over other acaricides for treatment of this infestation are now losing their efficacy due to development of resistant strains of ticks. MATERIALS AND METHODS: Boophilus microplus ticks with a previous history of acaricidal treatment especially synthetic pyrethroids (SP) such as cypermethrin, deltamethrin and flumethrin were randomly collected from different pockets of four Southern States of India namely Tamil Nadu, Kerala, Karnataka, Andhra Pradesh, and Puducherry from cattle. Deoxyribonucleic acid extracted from pooled adult B. microplus tick from each State was subjected to polymerase chain reaction-restriction fragment length polymorphism to detect point mutation in carboxyl esterase gene. RESULTS: A product size of 372 bp was obtained for cattle tick samples collected from all over Southern States of India. CONCLUSIONS: B. microplus ticks found in Southern part of India are not resistant to commonly used SP.