Naturally occurring Senna spp. toxicity in an Angus crossbred calf.

Ingestion of certain plants belonging to the genus Senna in animals can cause a rapidly progressive disease with myonecrosis. Natural senna intoxication was suspected in cattle that were grazing on contaminated pasture. Three calves presented with clinical signs of acute illness, characterised by sternal recumbency and absent patellar and withdrawal reflexes. Senna obtusifolia and Senna occidentalis plants were found in the grazing pastures. Serum biochemistry levels of creatine kinase and aspartate aminotransferase were higher than the reference ranges. Major pathologic findings included multifocal pale tan and dry skeletal muscle with severe segmental monophasic myonecrosis. Senna seeds were identified in the ruminal contents. A diagnosis of Senna intoxication was made given the clinical history and the compatible clinicopathological and pathologic findings. In addition, Senna plants in the pasture along with the Senna seeds were found in the ruminal contents in the affected heifer. [ABSTRACT FROM AUTHOR]