Experimental Ergotism in Sheep

Abstract

The oral administration of ergotamine to sheep at a daily dose of 1.0 mg/kg/day resulted in the death of 4. out of 6 animals within 10 days. Principal symptoms were anorexia, hyperventilation, cold extremities, salivation and, occasionally, tongue necrosis. Post-mortem examination of seriously affected animals revealed extensive intestinal inflammation. Ergot sclerotia were well tolerated by housed animals and at pasture in mild weather, even at dosages which contained a lethal amount of ergotamine. The only pronounced response to ergot, involving severe lameness and intestinal inflammation, was in an animal which was grazing pasture under cold wet conditions while receiving a dose of ergot containing only 0.5 mg ergotamine/kg/day. It is concluded that rumen conditions during the active fermentation of pasture grass allow the most efficient extraction of alkaloid from the ergot tissue, and that low environmental temperatures impair peripheral circulation so that the effects of ergotamine-induced peripheral vascular disturbance may become evident.