AVALIAÇÃO DA ATIVIDADE CARRAPATICIDA DO LAPACHOL CONTRA O CARRAPATO BOVINO (Rhipicephalus boophilus)

Abstract

Rhipicephalus (boophilus) microplus, popularly known as the bovine tick, is a major problem in Brazilian livestock farming, causing several economic losses in this branch. There are some ways to combat it, such as, for example, rotation of pasture, application of acaricides by contact, vaccines, treatment with homeopaths. However, these strategies have some disadvantages, such as high cost, the need for a specific professional, and the effectiveness of the product. Thus, the search for new ways to control the cattle tick is extremely important, since the main means of combat are not as effective or harm the animals or even the environment where they are, since they have in their composition active ingredients that can be offensive when applied inappropriately. Based on this problem, the molecules of natural origin and essential oils have gained prominence in research, because finding a molecule of natural origin that has acaricidal activity and can combat the tick without side effects on the animal and the environment, is of paramount importance for the ecosystem. In the present work we conducted tests using lapachol, which is a naphthoquinone found in some plants of the Ipê family. The methodology used this substance as a possible tick killer on bovine tick larvae. After extracting lapachol from purple ipê heartwood sawdust, tests were performed with concentrations of 1, 20, 40, 60, 80, 100, 250, 500, 1000, 10000, and 100000 ppm, and readings were taken in 24, 48, and 72 hours. The results indicated variations between the mortality of the larvae at the concentrations used. Furthermore, it is interesting to note that the presence of the control group, optimizations in the methods used, such as variations between concentrations, and the use of lapachol analogues may provide different results.