Investigation of suspected plant poisoning of North Sumatran cattle.
A variety of weeds was present on farms in the Karo district of North Sumatra where imported dairy cattle had died with liver damage thought to be due to pyrrolizidine alkaloid poisoning in early 1984. To determine which plant, or plants, might be responsible, six farms which had experienced one or more deaths were studied. An attempt was made to identify every plant available to the cattle at these sites and to assess their occurrence the different farms. All plants were screened for the presence of alkaloid-like material using spot tests and thin layer chromatographic (TLC) procedures. Forty-three plants from 17 families were collected and 25 of these were found to contain alkaloid-like material by TLC. Based on this chemical evidence, published information on the toxicity and the frequency of occurrence of plants at various sites, six plants Drymaria cordata, Ageratum conyzoides, Artemisia vulgaris, Eupatorium inulifolium, Mikania micrantha, and Emilia (Senecio) sonchifolia were considered high priority for further studies of hepatotoxicity.