Resumo

ARECE-GARCIA, Javier et al. Diagnosis of resistance to Albendazole sulfoxide in sheep and goats, in the Matanzas province. Pastos y Forrajes [online]. 2016, vol.39, n.4, pp.286-290. ISSN 0864-0394.

In order to evaluate the efficacy of Albendazole sulfoxide in the control of parasite infestation in sheep and goats, in vivo and in vitro studies were conducted in three sheep herds and a goat herd, in the Matanzas province (Cuba). In each herd, a fecal egg count reduction (FECR) trial and an egg hatching inhibition essay were carried out. For the in vivo essay 30 animals per herd with high nematode egg counts were selected, and two treatments with 15 animals each were randomly assigned: Albendazole sulfoxide (Labizol®, Labiofam, Cuba) in the recommended dose for sheep and goats, and a control group which was not dewormed. Eleven days post-treatment the animals were sampled to evaluate the FECR. For the in vitro trial feces were collected, anaerobically stored and the egg hatching inhibition was evaluated against serial concentrations of Albendazole sulfoxide, from 75 to 0,07 mg/mL. The FECR was calculated and the mean effective concentration (EC₅₀) was estimated. In the four herds Labiozol® could not reduce the egg count, with values that indicated resistance of the parasites to this drug (FECR lower than 95 % and/or its confidence intervals lower than 90 %) and absolute predominance ofHaemonchus contortus. The egg hatching inhibition study showed high variability in the EC₅₀, with values up to 1 000 times higher with regards to the lowest EC₅₀. It is concluded that in the studied herds there was evidence of the resistance of H. contortus to Albendazole sulfoxide.

Palavras-chave : hatching; Haemonchus contortus; eggs; nematodes.

        · resumo em Espanhol     · texto em Espanhol     · Inglês ( pdf ) | Espanhol ( pdf )