Abstract

ARECE, J et al. EVALUATION OF FOUR ANTIPARASITES AGAINST SHEEP GASTROINTESTINAL STRONGYLES. Rev Salud Anim. [online]. 2008, vol.30, n.3, pp. 180-183. ISSN 0253-570X.

In order to evaluate the efficacy of Levamisol 10%®, LABIOMEC®, Cydectin® and Virbamax® against gastrointestinal strongyles, a study was designed for which 45 Pelibuey sheep with a remarkable rate of parasite infestation were used. The animals were randomly distributed to form five groups which included, in addition to the drugs, a control group without antiparasitic treatment. The animals were weighed individually and the dosage was made according to the doses recommended for each product. A sampling was carried out the day of the treatment to determine the rates of parasite infestation with the modified McMaster technique, and feces pools were performed for each group in order to determine the genera present by means of coprocultures. In the tenth day post-treatment, a second sampling was made to evaluate the reduction of the faecal egg count (RFEC%). The determination of the efficacy was based on the recommendations of the WAAVP in which every product showing a RFEC lower than 95% or its confidence intervals lower than 90% is considered resistant. The efficacy in the reduction of parasite infestation of Virbamax® and Cydectin® was 100%, however there is a remarkable resistance rate to Levamisol 10%® and LABIOMEC® (87 and 61% RFEC for each product, respectively). In the case of Levamisol 10%, Haemonchus spp. was observed to be resistant, while LABIOMEC® showed multi-specific resistance (Haemonchus spp., Trichostrongylus colubriformis and Oesophagostomum columbianum).

Keywords : resistance; ivermectin; sheep; moxidectin; abamectin.