Natural and experimental poisoning by Cestrum laevigatum (Solanaceae) among cattle in the Agreste region of Paraíba, Brazil

Abstract

An outbreak of natural poisoning by Cestrum laevigatum was reported among cattle in the Agreste region of Paraíba, which affected six out of 20 animals. Four animals were found dead and two presented clinical signs, including, dyspnea, drooling, jugular vein engorgement, muscle tremors and ataxia, which subsequently progressed to recumbence and death. An experimental poisoning was performed in two bovines who were administered single doses of 35 g kg-1 and 50 g kg-1 body weight (BW), respectively, of fresh leaves and fruits. The animal that received 35 g kg-1 BW had mild clinical signs, consisting of apathy, salivation and reduced ruminal movements with recovery 30 hours after the onset of initial signs. The animal that received 50 g kg-1 BW showed apathy, dry stool, drooling, hyperexcitability, head pressing, opisthotonos, nystagmus, miosis, jugular and episcleral vessel engorgement, ruminal atony, muscle tremors, ataxia, falling, seizures, and sternal recumbence, followed by lateral recumbence, with death occurring 21 hours and 37 minutes after ingestion. The enzyme activities of aspartate aminotransferase and gamma-glutamyltransferase in the serum increased significantly 18 hours after the administration of the plant. The primary gross lesions in the natural and experimental cases were enlarged livers, with rounded edges and accentuation of the lobular pattern on the capsular and cut surfaces. Histopathology revealed diffuse centrilobular coagulative necrosis with hemorrhages and congestion, and the presence of degenerated hepatocytes in the midzonal regions. Based on the epidemiological and clinicopathological data, we concluded that C. laevigatum was responsible for an acute hepatotoxic disease among cattle in the Agreste region of Paraíba.