Evaluación in vitro del efecto acaricida de timol y carvacrol sobre la garrapata del ganado Rhipicephalus (Boophilus) microplus

Abstract

Abstract: The cattle tick, Rhipicephalus (B.) microplus, causes severe economic losses in cattle farms worldwide. This work reports an acaricide option based on two major components of some essential oils and whose biological activity has been previously reported. To evaluate the effect of thymol and carvacrol on the mortality of Rhipicephalus (B.) microplus larvae, replete adult females were collected manually in the parish of Guachanamá, canton Paltas, province of Loja, and kept at controlled temperature and humidity until the end of oviposition. The collected eggs were incubated to obtain larvae of 21 days old, which were used in the larvae package test with concentrations of 2.5, 5.0, 10.0, mg/mL of both compounds. At the concentrations of 10 mg/mL of thymol and carvacrol, larval mortality values were 84.76% and 98.2%, respectively. Strong positive correlations were obtained between mortality and concentration used (r=0.998 thymol; r=0.808 carvacrol). It is concluded that both thymol and carvacrol have an excellent acaricidal efficacy in vitro against Rhipicephalus (B.) microplus larvae.