Abstract

Trypanosoma evansi is the causative agent of Surra and the trypanosomiasis of domestic and wild animals and in Venezuela has a strong impact on livestock production. The objective of this study was to evaluate at parasitological and morphological level, the effect of aqueous extracts (AE) of garlic on T. evansi. For this garlic AE 20% was prepared and mixed with T. evansi infected blood from mice (108 trypanosomes/mL) to final concentrations of 2.5, 5 and 10%. The suspensions and controls were incubated at 37 °C for 1 hour and aliquots of them were used for the inoculation (500 trypanosomes/g of body weight) of mice (n=10) and for the scanning electron microscopy (SEM). The observations were made in a scanning electron microscope Hitachi S-4500 and parasitemia and survival of experimental and control groups were evaluated for 32 days. The 2.5% AE increased the prepatent period of infection, from 3 days (control group) to 10 days (experimental group). All of the control animals died by day 10, and 20% of those treated with 2.5% AE survived the infection from day 17 post-infection. The neutralization of infectivity by 5% and 10% AE was complete. The 10% AE produced contraction of the parasite, folding in on itself and surface alterations (pores and roughness). These results suggest that garlic AE modify T. evansi morphology and exhibits trypanocidal activity at 5-10% and trypanostatical at 2.5%.