ENGLISH YEW POISONING IN 43 CATTLE

Thirty-five privately owned to 2-year-old mixed-breed steers and heife rs, weighing 340 to 454 kg, died from accidental ingestion of English yew (Taxus baccata). Estimated dosages ranged from 0.36 to 0.70 g of f resh plant/kg of body weight. Clinical signs of poisoning and death be gan 2 to 3 hours after first exposure, and cattle continued to have cl inical signs, which ended in death 6 to 8 hours later. Most cattle had died by 4 hours after first ingestion. Necropsy of 4 cattle revealed substantial amounts of English yew leaves and small stems in the rumen contents. Grossly, there were areas of hyperemia in the abomasum and small intestine. Histologically, lesions were limited to the lungs and included moderate congestion and interlobular edema. Chemical analysi s by thin-layer chromatography of suspected yew plant material from th e rumen contents of the 4 necropsied cattle was compared to authentic taxol, and confirmed the presence of taxol in rumen samples.