【作者】 叶仕根；

【导师】 汪开毓； 何显荣；

【作者基本信息】 四川农业大学 ， 基础兽医学， 2002， 硕士

【摘要】 本试验研究了氧化鱼油对鲤鱼（60±10g）的病理学危害及饲料中添加维生素E对鲤抗氧化鱼油危害的保护作用。氧化鱼油有三个氧化程度，其过氧化物值（POV）分别为69.5、145.3、263.6 mEq O₂／kg oil（每公斤油脂中过氧化物相当于氧的毫克当量数）mEp O₂/kg oil，新鲜鱼油过氧化物值（POV）为3.6mEq O₂/kg oil；饲料维生素E有50、100、150IU三个添加水平，以50IU维生素E添加量为基础配方中的维生素E含量（参照NRC，1993．）。氧化鱼油的过POV越高，其对鲤鱼的危害越严重。当POV为69.5mEq O₂／kg oil时，发病率为16.7％，死亡率为10.0％；当POV为145.3mEq O₂/kg oil时，发病率为40.0％，死亡率为23.3％；当POV为263.6 mEp O₂／kg oil时，发病率为76.7％，死亡率为40.0％；新鲜鱼油试验组（3.6mEp O₂／kg oil）的发病率、死亡率均为零。维生素E有显著地抗氧化损伤作用，添加维生素E后，各氧化鱼油试验组的发病时间推迟，发病率、死亡率下降，症状减轻或不出现明显临床症状。氧化鱼油对鲤的危害主要表现为生长不良、瘦背病及以全身鳞片竖立、突眼、腹水为特征的渗出性素质样病变，并导致死亡。病理解剖司见肝脏肿大，颜色变淡，有针尖大至米粒大的白色坏死灶，后期呈绿肝症状；肾脏肿大，色泽变淡；肌肉萎缩、切面湿润，体侧红肌颜色变淡，纹理不清晰。组织学变化主要是肝组织空泡变性，出现溶解性坏死灶或凝固性坏死灶；胰腺腺泡萎缩、坏死；肾毛细血管扩张充血，并有出血；肌纤维萎缩，变性、坏死，肌纤维水肿，间隙显著增宽，排列紊乱。超微结构上，心肌纤维、肝细胞线粒体肿胀、扩张，结柯破坏，膜异常，线粒体内有糖原包含物。心肌细胞膜肿胀、扩张，间隙增宽，闰盘变浅甚至消失。骨骼肌肌纤维间隙扩大，排列紊乱。肝细胞核崩解，染色质变淡。肾小管微绒毛脱落，细胞内溶酶体增多。血液学检测表明，氧化鱼油使鲤的红细胞数（RBC）、血红蛋白含量（Hb）及血浆中维生素E含量下降，血浆丙二醛（MDA）含量升高。SOD、GSH-PX活性下降，但低POV（69.5mEq O₂/kg oil）组在试验前期（前8周）未见明显变化。更多还原

【Abstract】 Experimental fish diets contained 10% fish oil which had been oxidized to four degrees (peroxide values of 3.6,69.5,145.3 and 263.6 mEqO2/kg oil). There were three levels of Vitamin E (50,100,and 150 lU/kg diet) supplementation. The harm of the oxidized fish oil rose when its peroxide values increased. The conditions induced by oxidized oil were improved by the addition of vitamin E. The morbidities in the carp fed diets (Vitamin E of 50 lU/kg diet) were76.7%,40.0%,16.7%,0%,while the mortalities were 40.0%,23.3%,10.0%,0% ,respectively,for peroxide values of 263.6,145.3,69.5,and 3.6 mEqO2/kg oil. When the supplementation of Vitamin E is 100 lU/kg diets ,the morbidities were 23.3%,13.3%,0% and 0%,The mortality in the first group was 16.7%,while there was no death occurred in the other groups. The morbidities in the carp fed diets (Vitamin E of 150 lU/kg diets) were 6.7%,0%,0%,0%,while there was no death occurred in these groups. The fish fed diets containing oxidized fish oil exhibited poor growth,increase of mortality,reduction of lateral muscle and high incidence of exudates (generalized edema,exophthalmia,scale erection). Necropsy showed muscle atrophy,tumefaction in both the liver and kidney. Focal necrosis was occurred in the liver with the color being bluish. Red muscle fiber in the lateral body was discolored and its texture turned to be obscure. Histologically,great changes were appeared in the muscle fibers,liver and pancreatic tissue. Liver tissue showed vacuolation and coagulation or lytic focal necrosis;while pancreas tissue appeared acinus atrophy,degeneration,and necrosis. The blood capillary of kidney tissue took on dilatation,hyperemia and hemorrhage. The atrophy,degeneration and necrosis in the muscle fibers were significantly. The musclefibers were arranged disorderly. The interspaces of the fibers were enlarged significantly. Ultrastructurely,the mitochondria of cardiac muscle fiber and hepatocyte showed swelling,expanding,and disorganization. Cardiac muscle membrane were swellen and expanded. Its intermembranous space was enlarged. The intercalated disk was indistinct or extinct. Hepatocyte nucleus were fragmentized. The chromatin of hepatocyte was electron-lucent. The microvilli were sheded off from renal tubular epithelial cell. The lysosome in renal tubular epithelial cell was increased. Haematologically,the number of RBC,hemoglobin,and Vitamin E concentration in plasma decreased,while the MDA concentration in plasma increased. Plasma superoxide dismutase (SOD) and glutathione peroxidase (GSH-P) activities descended,while the SOD and GSH-PX activities of the fish fed diets containing 69.5 mEqOlkg oil were not affected by the oxidized fish oil during the fist 8 weeks.更多还原