Poisonous plants of livestock interest in the Amazonia and Savanna ecotone region Part II: Araguaína, North of Tocantins state, Brazil

Abstract

This study aimed to determine the poisonous plants of livestock interest in Araguaína region. A total of 87 farmers from 14 counties of northern Tocantins were interviewed and the properties were visited. According to reports, Palicourea marcgravii and Brachiaria decumbens were the main plants responsible for poisoning, in addition to outbreaks reports caused by Manihot esculenta, Ipomoea asarifolia, Enterolobium contortisiliquum, Pteridium aquilinum, Dimorphandra mollis, Stryphnodendron obovatum, Ricinus communis, and Palicourea juruana were also relevant. The apparently less important plants were Ipomoea setifera, Manihot glaziovii, Senna occidentallis, Enterolobium gumiferum, Crotalaria sp. e Asclepias sp. Among the plants reported as poisonous to cattle, but without toxicity yet established were mentioned Buchenavia tomentosa as a cause of abortion and death, Parkia pendula as a cause of incoordination, Psychotria colorata and Samanea tubulosa as abortive and Mucuna pruriens as responsible for mucosa irritation. It is concluded that the outbreaks by poisonous plants at the ecotone region of Amazonia and Savanna show particular characteristics although presents certain similarity to other regions of Brazil. This study revealed the presence of plants with the toxicity not established yet and the outbreaks occurrence related to them shows the importance to livestock and deserve to be investigated. Although the farmers have some knowledge of main poisonous plants, the high incidence of outbreaks in the region shows that there is a lack of studies aimed at prevention and control of poisoning to avoid economic losses. Keywords: Cattle, poisoning, ruminant, toxicology.