Poisoning by Sessea brasiliensis Toledo in cattle

Abstract

Mortality in cattle diagnosed as poisoning by the shoots of Sessea brasiliensis Toledo was studied. The toxicity of the shoots of S. brasiliensis was demonstrated experimentally. The experiments consisted in oral administration of different amounts of the shoots to nine calves and yearlings. Clinical observations were made and in the cases of death post-mortem examinations and histopathological studies were performed. The smallest dose which caused death was 32 /kg. The largest dose which did not cause even symptoms of poisoning, was 28,5 g/kg. The symptoms of the experimentally induced poisoning started about 12 hours after ingestion of the plant. These were apathy, anorexia, reduction of the frequency and intensity of the rumen movements, muscle tremors and staggering gait. The animals died during the experiments, two animals within about 24 hours and one in less time after the onset of the first symptoms. The main post-mortem findings were a nutmeg appearance of the cut surface of the liver, dry contents in the omasum, edema of the gallbladder wall and hemorrhages in various organs. The main histopathologic lesion was central lobular necrosis of the liver; Attention is called to the fact that S. brasiliensis poisoning of cattle is very similar to the one caused by Cestrum laevigatum Schlecht., an important poisonous plant in Brazil. The two plants have not been seen to occur simultaneously in the same area. This is important for the differential diagnosis of poisoing from these two plants.