Spontaneous and experimental poisoning of cattle by Palicourea aeneofusca in the region of Pernambuco and induction of conditioned food aversion

ABSTRACT: The objective of this study was to describe the epidemiological, clinical, and pathological aspects of Palicourea aeneofusca poisoning in cattle in the region of Pernambuco, Brazil and to determine if it is possible to induce food aversion by P. aeneofusca poisoning in cattle raised under extensive management conditions. To determine the occurrence of poisoning, 30 properties were visited in five municipalities of the region of Pernambuco. Three outbreaks of poisoning of cattle were monitored. To induce conditioned food aversion by the consumption of P. aeneofusca, 12 animals were randomly distributed into two groups of six animals each. Cattle were weighed and received green P. aeneofusca leaves in their trough at a dose of 35mg kg-1 body weight for spontaneous consumption. The control group (CG) animals received water (1ml kg-1 body weight) via a feeding tube after the first ingestion of the plant, while the other animals, constituting the aversion test group (ATG), underwent induced aversion with lithium chloride (LiCl - 175mg kg-1 body weight) via a feeding tube. For the ATG cattle, the aversion to P. aeneofusca induced by a single dose of LiCl persisted for 12 months. In contrast, the CG animals continued to consume the plant in all tests performed, indicating the absence of aversion. This study showed that aversive conditioning using LiCl was effective in preventing poisoning by P. aeneofusca for a period of at least 12 months.