In vitro acaricidal activity of Piper tuberculatum against Rhipicephalus (Boophilus) microplus

Rhipicephalus (Boophilus) microplus has a strong impact on bovine health. The aim of this study was to evaluate the in vitro acaricidal activity of Piper tuberculatum extracts on R. (Boophilus) microplus ticks obtained from cattle. The adult immersion test (AIT) was used to estimate the inhibition of oviposition. Moreover, the larval package test (LPT) was performed. P. tuberculatum extracts at 100 mg/ml showed a mortality of 78% after 24 h in adult ticks, reaching 100% at 9 days. Moreover, the mortality rate was signi?cantly different (p<0.001) among the tested groups at 11 days. Probit regression analysis showed that the mean lethal concentration (LC50) of P. tuberculatum extracts was 20.30 mg/ml after 24 h. On day 11, there were signi?cant differences in oviposition rate among the groups, with 56% oviposition in the control group, whereas no oviposition was observed (p<0.01) in the groups treated with P. tuberculatum at 100 mg/ml. In the LPT, high mortality (56.00%) was found in the group treated with P. tuberculatum (50 mg/ml), whereas the control group had 2.67% (p<0.01). The use of P. tuberculatum extracts (100 mg/ml) was highly effective as an acaricide, reaching a high mortality rate in adult R. microplus ticks.