Cattle toxic plants

Herbivores possibly regulate the amount eaten from toxic plants and thus avoid ill effects. Cattle cycle between consuming large and small amounts of tall larkspur, D. harbeyi. The principal toxic alkaloid in tall larkspur is methyl-lycaconitine (Pfister etcj/., 1997). 

This part is certainly the least developed, to our knowledge. It is important to remember, however, that an animal may ingest a toxic plant and may also survive. If this is the case, and provided this animal or its production are intended for human consumption, one should be able either to analyze tissues and fluids for toxin residues or to monitor fluids (plasma, milk, urine) to determine whether this animal or its productions can be considered safe for human consumption. There are very limited examples of such occurrences. In our laboratory, we analyzed muscular tissues after a confirmed yew tree poisoning case (Taxtis baccata). Three animals did not display any significant trouble except for a transient depression, which resolved itself after 12 h. These animals were butchered and muscle samples were analyzed for taxin residues, as they were known to be exposed to it. Our analytical technique (extraction in alkalinized methylene dichloride) followed by TLC development based on a modification of a published technique (9685), showed that the muscle samples contained between 0.012 and 0.015 j.g/g taxin (wet weight). The presence of taxin in muscle tissues had never been previously reported in cattle after moderate poisoning. Based on this result, the meat was... 

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. 

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... 

In 1977, he published his last original paper on the structure of a quercetin triglycoside containing D-apiose, isolated from Solatium glaucophy-lum a plant toxic to cattle. In spite of this, his extraordinary capacity as a reader allowed him to remain up to date in a great variety of topics, not only in those of direct interest to him but in those that were studied by several graduate students working under different supervisors. 

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