INTOXICAÇÃO POR ANTIBIÓTICO IONÓFORO EM RUMINANTES ALIMENTADOS COM VARREDURA DE FÁBRICA DE RAÇÃO – RELATO DE CASO

Ionophore antibiotics (IA) are drugs used in animals, particularly as coccidiostats and growth promoters. They can cause acute or chronic poisoning, inducing skeletal and / or heart muscle injuries. This paper describes the epidemiological, clinical and pathological aspects of an IA poisoning outbreak in sheep and cattle fed with leftovers from a animal ration factory. Four hours after the access to the contaminated feed, some sheep were found dead and several others were sick. The cattle manifested clinical signs one day after ingestion of the feed, with death 4 to 20 days after clinical onset. The signs consisted of inappetence, weakness, reluctance to move, incoordination, dyspnea, lateral decubitus and death. Of the sheep herd 61 (42.36%), and eight young cattle (24.24% of the lot) died. Two sick sheep were sent to the Veterinary Pathology Sector, Department of Veterinary Medicine of the Federal University of Lavras (SPV/DMV/UFLA). Due to the severity of the clinical condition, both were euthanized. At necropsy were observed pale areas in the muscles, characterized histologically by varying degrees of necrosis and regeneration in skeletal and cardiac muscles. It was performed a chromatographic analysis (HPLC) of a sample of feed, which showed 97.14 mg monensin/kg of feed. The diagnosis was based on epidemiological, clinical, gross and histological findings, and toxicological analysis of the feed used. Although the use of "scan feed mill" seems an economically attractive option for producers it presents risks and is not recommended