Avaliação do potencial anti-helmíntico de Origanum vulgare e Eugenia uniflora em nematódeos gastrointestinais de ruminantes

Abstract

This study aimed to evaluate the in vitro effects of Origanum vulgare extracts on gastrointestinal nematode of cattle and the in vitro and in vivo action of Eugenia uniflora extracts in Haemonchus contortus as well as estimating its toxicity in VERO cells. For the in vitro analysis of different hydroalcoholic and aqueous extracts, the technique of inhibiting the hatchability of gastrointestinal nematodes eggs was applied; the Origanum vulgare and the Eugenia uniflora extracts were tested in the concentration of 0.62-80 mg/mL and 1.25-40 mg/mL, respectively. Commercial anthelmintics and distilled water were used as control treatments. The cytotoxic effect of E. uniflora extracts was measured by using MTT assay (thiazolyl blue tetrazolium bromide test) in VERO cells. The in vivo test was conducted with naturally infected sheep receiving 100 mg/kg of the hydroalcoholic extract by maceration of E. uniflora administered orally for three consecutive days; fecal collection was performed to estimate the reduction in EPG. Test results showed that the O. vulgare extracts inhibited egg hatch of cattle gastrointestinal nematodes at a percentage that varied from 8.8 to 100%. The extracts of E. uniflora also inhibited the hatchability of H. contortus eggs, with an action level ranging from 14.56 to 99.75%. The extracts have shown moderate to null cytotoxicity, ranging from 51.23 to 100% viable cells. It was not observed the reduction of the EPG for the treatment group in the in vivo test, only for the positive control group with anthelmintic. The different O. vulgare and E. uniflora extracts have proved to be effectual on the in vitro inhibition of the hatchability of nematodes eggs in ruminants, with O. vulgare dye and hydroalcoholic extract being the most promising methods for gastrointestinal nematodes control in cattle and hydroalcoholic extracts of E. uniflora for H. contortus eggs.