肉鸡实验性镉中毒的病理学研究

PATHOLOGY OF EXPERIMENTAL Cd POISONING IN BROILER CHICKENS

用 3日龄雏鸡 15 0只 ,作急性和亚急性镉中毒病理学观察 ,急性毒性的LD50 为 84 4 8mg/kg体重。 1/ 10 ,1/ 2 0 ,1/ 30 ,1/ 40LD50 和基础组作亚急性实验 ,实验期 6周 ,死亡和存活鸡之比分别为 4 / 12 ,3/ 12 ,3/ 12 ,3/ 12和 0 / 12。死亡鸡的主要病变为肺充血、出血及炎症 ,肝变性及肝周炎 ,心肌变性及心外膜炎以及肠道卡他等。电镜检查亚急性存活病例 ,主要肝、心、肾细胞内的线粒体减少及萎缩 ,肝内质网增生、断裂 ,肾小球基底膜节段性增厚。亚急性试验鸡的肝和肌肉中镉含量极显著差异高于对照组 (P <0 0 1) ,而肝中铁含量试验组则极显著低于对照组 (P <0 0 1)。

three day old broiler chickens were made experimental Cd poisoning.LD50 of acute Cd poisoning was 84 48 mg/kg body weight.Subacute Cd poisoning was with 1/10,1/20,1/30 and 1/40 LD 50 groups and basal diet group containing Cd 0 114 mg/kg,the mortality were 4/12,3/12,3/12,3/12 and 0/12,respectively.Clinic symptoms of the affected chickens appeared as anemia,reduced growth,diarrhea and dyspnea.Pathologic lesions of acute dead cases were hypermia and hemorrhage and inflammation,degeneration of the liver,heart and kidneys,gastroenteritis,hyperemia and hemorrhage of the brain.Pathologic lesions of subacute cases were characterized by interstitial pneumonia and fibrinous pleuropneumonia,fibrinous epicarditis and catarrhal enteritis.Ultrastratural changes of subacute cases showed that mitochondria of the liver cells,cardiac muscle fibers decreased and atrophied.The endoplasmic reticulum was hyperplastic and fragemented.The thickness of basal membrane of the kidney glomerulus was increased also.Cd contents of the liver and thoracic muscle,compared with these of the control group,increased significantly(P<0 01).Fe content of the liver,compared with that of the control,decreased significantly (P<0 01).