Toxicity of Thermopsis montana in cattle.

Cattle had severe signs of toxicosis when gavaged dried ground Thermopsis montana (false lupine, poison bean, mountain thermopsis) at doses of 0.6-2.8 g/kg/day in a water suspension. Signs included depression, anorexia, swollen eye lids, arched back, tucked abdomen, rough hair coat, and in extremis a prolonged recumbency lasting up to 9 days. Plant potency varied among collections. Total alkaloid doses in collections eliciting severe signs varied from 1.1-11.3 mg/kg/day. There were 5 major alkaloids in each collection that varied in concentration among the collections perhaps accounting for variation in severity of signs elicited. Four of the alkaloids were identified by GC retention time, MS fragmentation patterns and OR analysis as N-methylcytisine, cytisine, (-)-thermopsine, and (-)-anagyrine. Measurements showed a very marked increase of 10X-20X in levels of certain serum enzymes--SGOT, CPK, and LDH that persisted during the period of maximum clinical signs.