Spontaneous Crotalaria incana poisoning in cattle in the state of Paraná, Brazil

Abstract

Plants of genus Crotalaria have been reported as poisonous for many species of domestic animals. The aim of this work is to report, for the first time in Brazil, an outbreak of C. incana poisoning. The outbreak took place in Nova América da Colina County, Northern region of Paraná state, Brazil, causing death of 30 Nelore heifers in a herd of 223 animals, between 3 and 5 years old. The animals were grazing on pasture fully infested with C. incana. The main clinical signs were characteristic of hepatic encephalopathy and consisted of blindness, depression, aggressiveness, recumbency and death in 48 hours. Gama-glutamyltransferase, and alkaline phosphatase activities were increased. The main necropsy findings were liver congestion and evident lobular pattern, increased gall bladder volume and mesentery oedema near gall bladder. Histological exams showed hepatic hemorrhagic centrolobular necrosis, megalocitosis and spongiform degeneration in thalamus. Morbidity and lethality rates were, respectively, 13,45% and 100%. Epidemiological, clinical and pathological findings suggest that C. incana poisoning was the cause of illness.