In vitro anthelmintic activity of Pimienta dioica and Origanum vulgare essential oils on gastrointestinal nematodes from sheep and cattle

The aim of the study was to evaluate the in vitro nematicide activity of the allspice (Pimienta dioica) and oregano (Origanum vulgare) essential oils (EOs) on eggs and larvae of gastrointestinal nematodes (GIN) from ruminant. The EOs were obtained by hydro-distillation of previously dehydrated plant material. In the in vitro evaluation, the egg hatching and larval mobility of Haemonchus contortus and Cooperia spp. of sheep and cattle, respectively, were determined. EOs at concentrations of 20.2–252.3 µg µL−1 with serial dilutions were used, also a negative control (distilled water + Tween 20) and Thiabendazol (77 µg µL−1) and Levamisole (120 µg µL−1) as a positive control to eggs and larvae, respectively, were placed on microplates. The results were analyzed with the PROBIT procedure. PPEO showed ovicidal effect in vitro test, with lethal doses 99 (LD99) of 0.56–4.19 µg µL−1, while oregano essential oil (OREO) was shown to be a larvicidal activity with doses of LD99 of 0.15–6.60  L−1. The results confirm that P. dioica and O. vulgare EOs have ovicidal and larvicidal capacity against GIN in vitro test.