Anthelmintic resistance of cyatostomas (small strongyles of equine) to fenbendazole

Abstract

A case of anthelmintic resistance of Cintostomas to Fenbendazol and side resistance to Albendazol is described. The farm, is located in the Department of Florida and has an area of 320 has. and runs 120 equids of different cattegories mainly on native pastures. A deficiency of parasite control was clinically suspected. Fourty young horses were divided into four equilibrated groups in terms of eggs per gram (E.P.G.) values and randomly assigned to the following treatments: Control. Ivermectina, Fenbendazol and Pirantel. The resistant were detected by the fecal egg count reduction (FECR) test. The arithmetic mean for the "0" and "14" days and their respective FECR were: I) Control group 1870 1810, II) Ivermectin group 1700 100%, III) Fenbendazol group 1689 2020 0%, IV) Pirantel group 1640 360 77%. The larval cultures showed: I) Control group 89%, Cintostomas sp. 10%, Strollgylus equinus and 1% Trichostrongylus axei. III) Fenbendazol group 100% Ciatostomas sp. IV) Pirantel group 100 % Ciatostomas sp.. Following, it was observed the FECR for the Albendazol (29 %). II was concluded Cintostomas sp. were resistant to fenbendazoL side resistant to albendazol, and showed sensibility to ivermectina and an erratic behaviour to pirantel.