Efficacy of essential oil of Lippia sidoides (Verbenaceae) for controlling the cattle tick Rhipicephalus (Boophilus) microplus on naturally parasitized animals under field conditions.

Abstract

Efficacy of the essential oil of Lippia sidoides to control the bovine tick Rhipicephalus (Boophilus) microplus was evaluated in tests on naturally infested cattle under field conditions. Twenty cattle were allocated to one of two groups (Control and Treated). Animals in the treated group were sprayed with three liters of 1 % L. sidoides solution (10,000 ppm) and efficacy was calculated from teleogynous counts between 4.5 and 8 mm in length before (days -3, - 2 and - 1) and after treatment (days +3, +7, +14, +21 and +28). The essential oil of L. sidoides showed an average efficacy of 50.7 % between days + 3 and + 21, with greater efficacy in the larvae (63.2 % - p = 0.0001).