Avaliação in vitro da ação do óleo essencial de capim limão (Cymbopogon citratus) sobre o carrapato bovino rhipicephalus (Boophilus) microplus

Abstract

The indiscriminate use of chemical products to control the cattle tick is the main cause of the gradual increase in the number of strains of this parasite that are resistant to the bases currently available in the market. The use of essential oils and plant extracts is an ancient practice for tick control; however, only recently has it received due attention by researchers. The aim of this experiment was to evaluate the in vitro efficacy of lemongrass (Cymbopogon citratus) essential oil on engorged females of Rhipicephalus (Boophilus) microplus through immersion test. Six concentrations of Cymbopogon citratus oil (1; 5; 10; 25; 50 and 100%) were tested against a tick population resistant to synthetic formamidines and pyrethroids. The inhibition of egg-laying was 3; 23; 46; 66; 46 and 46%, the hatching was 83; 58; 31; 0; 38 and 25%, and the treatment efficacy was 32; 64; 83; 100; 88 and 82%, respectively. C. citratus oil showed partial control of the tick R. microplus in vitro, even against populations resistant to chemical products.