Amorimia (Mascagnia) septentrionalis contains sodium monofluoracetate and when consumed by ruminants cause outbreaks of sudden death. This study aimed to describe the epidemiology, clinical and pathological signs of outbreaks of sudden deaths in cattle caused by A. septentrionalis in the states of Pernambuco and Paraíba. For this, technical visits where made on various properties in the regions of Médio Capibaribe/PE and Itabaiana/PB. Eight cattle were necropsied. Tissues were collected from abdominal and thoracic cavities, besides brain and spinal cord. The clinical changes consisted in apathy, prolonged sternal recumbency, reluctance to move, fatigue, tachypnea, tachycardia and positive venous pulse. The animals that were forced to move showed instability, muscular tremors and then a single fall followed by vocalizations, paddling and death in 5-7 minutes. Macroscopic changes consisted in pulmonary edema, globular heart with whitish areas, petechiae and ecchymosis in the epicardium, myocardium and papillary muscles. Microscopically there was an increase of eosinophilia of cytoplasm of cardiomyocytes, picnosis, cariorrexia, karyolysis, loss of striations and multifocal areas of cardiac fibrosis. In the kidney, there was hydropic vacuolar degeneration and necrosis of epithelial cells in convoluted tubules. The clinical signs presented by the cattle poisoned were similar to those previously described by plants containing MFA. The macroscopic and microscopic lesions described in the heart and kidneys are of great diagnostic value. A. septentrionalis is the main toxic plant of livestock interests in the studied regions due to direct and indirect economic losses in livestock that causes.
Poisonous plants; Amorimia septentrionalis; plant poisoning; sudden death; MFA; cardiac fibrosis; cattle