Experimental poisoning by Dodonea viscosa (Sapindaceae) in cattle

Abstract

As folhas de Dodonea viscosa foram administradas por via oral a cinco bovinos, dos quais quatro receberam folhas verdes frescas e o quinto, folhas secas. Quatro animais apresentaram sinais clínicos e morreram, enquanto o quinto bovino não adoeceu. A planta verde fresca mostrouse tóxica a partir de 25g/kg. Todos os animais que morreram, manifestaram sinais clínicos entre 13h30min e 45h após a ingestão das folhas. A evolução clínica foi de aproximadamente 8h30min. Os animais manifestaram apatia, anorexia, leve tenesmo, tremores musculares, dificuldade para permanecer em estação pressionando a cabeça contra obstáculos, decúbito esternal, movimentos de pedalar, coma e morte. A alteração macroscópica mais significativa foi observada no fígado, com acentuação do padrão lobular, áreas vermelho- escuras intercaladas com áreas vermelho-claras, dando um aspecto de fígado noz-moscada. Hemorragias petequiais foram encontradas em serosas de órgãos da cavidade abdominal e torácica bem como no intestino. A principal alteração microscópica observada foi necrose hepatocelular coagulativa centrolobular ou massiva, associada à congestão e hemorragias.The leaves of Dodonea viscosa were force fed to five bovines. Four received the leaves in fresh green stage and the fifth dried ones. Clinical signs were observed in four of the bovines that died; the fifth did not show signs of poisoning. The fresh green plant was proved to be toxic from a dose of 25g/kg on. Dried leaves fed at the dose of 30 g/kg were also toxic. All the animals that died showed clinical signs from 13h30min to 45h after the ingestion of the plant and and death followed within about 48h. The clinical course lasted for about 8h30min until death. The main symptoms where apathy, anorexia, slight tenesmus, muscle trembling, difficulties to keep consciousness, pressing the head against obstacles, lateral recumbency, paddling movements, coma and death. The most significant macroscopic alterations were observed in the liver, with accentuation of the lobular pattern, dark-red areas interspersed with yellowish areas. Petechiae were found in serosal membranes of the abdominal and thoracic organs as well as the intestines. The main microscopic change was hepatic centrolobular coagulative necrosis, associated with congestion and hemorrhages