Nematoda Cyathostominae parasito de equinos no estado do Rio de Janeiro: comprovação e resistência a compostos benzimidazóis a nível de campo

Abstract

The objective of the present study was to evaluate the efficacy of benzimidazole compounds against small strongyles (Cyathostominae) parasites of horses. The study included 8 farms located in the State of Rio de Janeiro and a total of 127 horses. The following benzimidazoles anthelmintics were used: fenbendazole paste, fenbendazole powder included in feed at dose rate of 7.5 mg/kg body weight, a combination of fenbendazole and trichlorfon paste, using 7.5 mg/kg and 22.5 mg/kg body weight, respectively, and oxibendazole paste, 10.0 mg/kg body weight. The studies were based in the reduction of fecal egg counts of the horses after treatment with the different compounds and formulations. The results showed different degree of resistance of small strongyles (Cyathostominae) to fenbendazole and to oxibendazole. Field resistante strain of cyathostominae to oxibendazole were also detected.