Mahdi Deljou - Department of Clinical Sciences, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
Mohammad Reza Aslani - Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahrekord University, Shahrekord, Iran
Mehrdad Mohri - Department of Clinical Sciences, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
Ahmad Reza Movassaghi - Department of Pathobiology, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran
Mohammad Heidarpour - Department of Clinical Sciences, School of Veterinary Medicine, Ferdowsi University of Mashhad, Mashhad, Iran

Toxic effects of monensin, a polyether antibiotic mainly used as a coccidiostat, have been described in a wide range of animals. The present study was performed to investigate the toxic effects of monensin in goats. Seven adult goats were administered sodium monensin, ۱۳.۵ mg kg-۱, daily for five consecutive days via gastric gavage. Monensin toxicity was evaluated by clinical signs, serum biochemistry and pathology. Monensin exposure caused diarrhea, tachycardia and reduction in ruminal movements and body temperature. Significant increase of creatine kinase, lactate dehydrogenase, aspartate aminotransferase, total bilirubin, blood urea nitrogen, creatinine and erythrocyte superoxide dismutase were observed in monensin exposed goats. Reduction of erythrocyte glutathione peroxidase and elevation of serum malondialdehyde and troponin I were inconsistent. In necropsy, there were effusions in body cavities, vacuolar degeneration and coagulative necrosis in cardiac and skeletal muscles and renal tubular necrosis. These findings suggested that monensin intoxication in goats leads to cardiac, skeletal and renal damage and a wide range of biochemical abnormalities. Oxidative stress may be involved in the pathogenesis of monensin poisoning.

Cardiomyopathy, Goat, Monensin, Oxidative stress, Poisoning