Cerebral infarction in a steer associated with consumption of Leycesteria formosa (Himalayan honeysuckle)

A mob of 60 Highland cattle had been grazing pasture and Leycesteria formosa (Himalayan honeysuckle). Two cows were found dead; post-mortem examination revealed renal infarcts. A recumbent steer appeared to recover with treatment but then developed neurological signs, including ataxia, circling and blindness. Five months later, with no improvement in the clinical signs, the steer was humanely killed, and the brain examined. The temporal and occipital lobes of the right cerebral hemisphere were absent, leaving only the olfactory cortex. Histopathology revealed chronic thrombosis and recanalisation of the internal carotid artery, consistent with cerebral infarction. Toxins within the plant are a possible cause of endothelial damage resulting in infarction of tissue.