Poisonous plants and their metabolites causes huge economic losses In the livestock industry worldwide. Intake as in other cases of poisoning from poisoning caused by plants is important. Some plants show the lethal effects of even small amounts, but generally most of plants either not poisonous or very little adverse effect on the digestive system.Herbal poisons based on to the impact of chemical structures and the living; alkaloids, glycosides, glucosinolates, phenolic compounds, photosensitive substances, toxic proteins and peptides, amino acids, vitamins, disrupts the use of vitamin substances, substances that disrupt the use of minarels, toxic fatty acids, resinous substances and others may be classified. To prevent the risk of consumption by animals or minimization of toxic effect, determining the measures to be taken for effective management in the region and it is necessary to raise the general level of knowledge about poisonous plants. Poisonous plants, which are subject to very different classification examined. A variety of plants give rise to adverse effects on the digestive system, either directly or indirectly by affecting other organs. The result of the effect of this plant in the digestive tract; hypersalivation, colic, gastritis, enteritis, swelling, constipation, diare that one of these symptoms, some or all may ocur. Under these headings, plants in the direct effect on the digestive system will be examined by the toxic substances it contains.