Trema Orientalis Intoxication in Goats

• Main Authors: Ching-Yao Huang, 黃敬堯
• Other Authors: Chian-Ren Jeng, D.V.M., Ph. D
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/80495801606309731013

碩士 === 國立臺灣大學 === 獸醫學研究所 === 89 === Trema orientalis is a deciduous tree belonging to the family of Ulmaceae. The plant is edible and medicinal however, suspected cases of Trema orientalis intoxication in goats have been reported in eastern Taiwan recently. The lesions were somewhat similar to those caused by Trema aspera, the other plant of Ulmaceae, well known for its hepatotoxicity in herbivores in Australia. In order to clarify the possible toxicity of Trema orientalis in goats, a series of examination including clinical signs, hematology, blood chemistries, and pathology were performed in both short and long-term feeding studies. There were severe depression, anorexia, and weight loss in the goat fed leaves of Trema orientalis of a dose of 10g/kgBW/day or higher. The animals were dead one or two days after present with clinical signs. There were no significant clinical signs in the goat fed with 4g/kgBW/day or lower level of leaf. The increased serum level of gamma glutamytransferase (GGT) were correlated with the appearance of clinical signs and histopathological changes. Changes in hematological profiles did not correspond very well with injury of Trema orientalis. Grossly, swelling and yellow discoloration of the liver were the most significant lesions in the goat dying spontaneously after feeding Trema orientalis. Occasionally, petechia and ecchymosis presented in the liver of some of the goat. Histopthologically, there were multifocal lobular necroses in the liver featured with acute hepatocellular lysis, pyknosis and karyohexis in necrotic cells, presence of homogenous eosinophilic debris, and fatty change in the remaining viable cells. The extensiveness of hepatic lesions were in parallel with the amount of leaves consumped. In higher dose, the lesions were more extensive and only hepatocytes in the periportal area were spared. In the lower dose, the lesions more localized in the centrilobular area. Only individual cell necrosis and degeneration were found in the long-term study (50g/goat/day). Ultrastructurally, there were varied changes in the hepatocytes, which included lipid droplets, formation of myelinoid body, lysosomes and residual bodies, cup-shaped mitochondria, and flocculent densities in mitochondria. The study demonstrated that T. orientalis is indeed poisonous to goats with liver as the major target organ. The animal may suffer from acute liver damage and die soon after feeding with large amounts of leaves (10g/kgBW/day). However, the toxic effect of T. orientalis seems not accumulative since no significant hepatocellular injury was revealed functionally and morphologically following consumption of a low level of leaves at 50g/goat/day for a long period of time. The study suggests the hepatocellular injury caused by T. orientalis may be secondary to damage of mitochondria that may subsequently cause irreversible disturbance of energy metabolism and lead to hepatocellular necrosis. An incidental finding in this study was that native Taiwanese goat appeared to be insusceptible to T. orientalis because no functional or morphological hepatic injury was revealed even at a dose of 20g leaves/kgBW/day.