Sheep toxic plants

Thesiuside (bufadienolide triterpene) Thesium lineatum (Santalaceae) toxic plant (sheep poisoning) Na+, K+-ATPase [toxic]... 

Plants that contain furanocoumarins have been implicated in several problems of livestock poisoning. For example, in the western United States, Cymopterus watsoni (Apiaceae) has been involved in the poisoning of sheep (Ivie, 1978). Starved individuals of the rock hyrax, Procavia capensis syriaca, which is notable for its ability to consume toxic plants, were killed when they consumed shoots of Pitur-anthos triadiatus (Apiaceae), which contain furanocoumar-... 

Today, the use of toxic plants for intentional poisonings are rare. In fact, accidental poisonings (exclusive of drug overdose) of humans as the result of natural toxins from plants or animals accounted for only 51 deaths among the 6,043 deaths reported for poisonings by all types of substances in 1988 (National Center for Health Statistics, 1991). While the impact of poisonous substances in plants on humans has been reduced in significance, the same can not be said for domestic animals. It is estimated (Nielsen and James, 1992) that the total annual death attributable to poisonous plants exceeds 250,000 animals per year for cattle and for sheep in the United States. These losses translated to an estimated direct economic loss in excess of 240 million dollars in 1989. 

In mammals, phenobarbital and phenytoin increase serum ceruloplasmin concentrations (Aaseth and Norseth 1986). Chronic copper poisoning in sheep is exacerbated when diets contain heliotrope plants (Heliotropium sp., Echium spp., Senecio sp.). Aggravated effects of the heliotrope plants include reduced survival and a twofold to threefold increase in liver and kidney copper concentrations when compared to control animals fed copper without heliotropes (Howell et al. 1991). Rats given acutely toxic doses of 2,3,7,8-tetrachlorodibenzo-para-dioxin had elevated concentrations of copper in liver and kidney because of impaired biliary excretion of copper (Elsenhans et al. 1991). Morphine increases copper concentrations in the central nervous system of rats, and dithiocarbam-ates inhibit biliary excretion (Aaseth and Norseth 1986). In human patients, urinary excretion of copper is increased after treatment with D-penicillamine, calcium disodium EDTA, or calcium trisodium diethylenetriamine penta acetic acid (Flora 1991). 

Se excess Tuva region Increasing Se content in sandy Dystrict Kastanozems, up to 2-4 ppm. Increasing Se content in plants, up to 13 ppm Deformation of hoofs, wool cover losses, hypochromic anemia. Selenium toxicity in sheep and cattle... 

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