Multirresistant population of Rhipicephalus (Boophilus) microplus ticks in Uruguay

Abstract

The results of resistance diagnostic tests of Rhipicephalus (B.) microplus ticks to acaricides, performed at Dirección de Laboratorios Veterinarios “Miguel C. Rubino”, between 2009 – 2013 are shown. Evolution of this process in the country (30º-35º Lat. South, 53º-58º Long. West ) is described. Up to 2006, resistance to organophosphates, synthetic pyrethroids and mixtures was exclusively determined. In 2006 the first diagnosis of resistance to fipronil was performed, followed by amitraz (2009) and macrocyclic lactones (2010). No lack of efficacy has been determined for the fluazuron molecule, present in the Uruguayan market since 1996. In 2009, the first multiresistant tick population was diagnosed. Despite the fact that this situation is considered as emerging, it represents a serious risk of availing of a technical feasibility in the fight against this parasite. Application of sustainable control strategies is considered important in order to maintain the therapeutic efficacy of the products.