Recent investigations into the toxicity of known and unknown poisonous plants in the Union of South Africa VIII

Abstract

Chemical tests and drenching and feeding experiments were conducted with fourteen different plants. It is significant that hydrocyanic acid was detected in specimens of wilted Medicago sativa L. (lucerne), Tephrosia macropoda E. Mey (fish poison); and Atriplex semibaccata R.Br. (creeping salt bush), whilst none was detected in fresh specimens of these plants. The possibility of hydrocyanic acid poisoning through the eating of these plants in the wilted state must, therefore, be considered . No hydrocyanic acid was detectable in fresh specimens of Tephrosia Vogelii Hook. Acalypha indica L. is a deadly poison, the active principles being hydrocyanic acid (cyanogenetic glucoside) and a substance causing intense dark chocolate-brown discolouration of the blood, and gastrointestinal irritation. Large amounts of bulbs of an Urginea sp. (O.P.H. No. 5603; 23.9.36) caused transient symptoms of poisoning in a sheep. The results of feeding and drenching experiments conducted with the following plants were negative: Crassula expansa Ait., Melica decumbens Thunb., Canavalia ensiformis DC., Ornithogalum Pretoriense Bkr., Argemone Mexicana L., Rumex ecklonianus Meisn.