In vitro biological activity of hydroalcoholic extracts from Caesalpinia ferrea and Lippia origanoides on adults of Bovicola caprae (Gurlt, 1843) (Mallophaga: Trichodectidae)

The conventional control of Bovicola caprae consists of using chemical insecticides, which often becomes ineffective due to the development of resistance, stimulating the search for alternative control methods. This study evaluated the in vitro bioinsecticidal potential of hydroalcoholic extracts from Caesalpinia ferrea and Lippia origanoides against adult B. caprae. The extracts of C. ferrea and L. origanoides were obtained from the fruits and leaves, respectively. Specimens of B. caprae (80 per group) were exposed to five different concentrations of each extract. The tests were conducted in duplicate, using distilled water (negative control) and deltamethrin (positive control) as control groups. Mortality was assessed at 2h, 4h, 6h, 12h, 24h, and 48h after exposure to the products. Both extracts caused mortality in the lice. Total mortality was observed after 6h of exposure to L. origanoides extract at 130 mg/mL. C. ferrea presented an LC50 of 67.82mg/mL up to 4h and caused total mortality at a concentration of 78.75 mg/mL from 12h after exposure to the hydroalcoholic extracts. Due to the insecticidal activity observed, both extracts are considered promising for the control of this ectoparasite.