【作者】 朱金娈；

【导师】 邹晓庭； 许梓荣；

【作者基本信息】 浙江大学 ， 动物营养与饲料科学， 2003， 硕士

【摘要】 本课题以产蛋期肉种鸡为试验对象，首次研究了二氢吡啶对蛋鸡脂肪肝和脂肪代谢的影响，并探讨其作用机理。 选300日龄肉种鸡540羽，随机分成3组(每组设4个重复，每个重复45羽)，分别饲喂含0(对照组)、150mg／kg和300mg／kg二氢吡啶的玉米—豆粕型饲粮。自由采食、饮水和16h光照，预试期7天，正试期90天。 饲养实验结束后，每组选取体重相近的试验蛋鸡12羽，共36羽，心脏采血制取血清，测定血清中相关生化指标和激素水平。屠宰取肝脏样品，测定肝脂率、超氧化物歧化酶(SOD)活性、载脂蛋白AⅠ和载脂蛋白B含量、cAMP含量、线粒体MDA含量、线粒体膜流动性；取腹脂，计算腹脂率、测定激素敏感脂肪酶(HSL)活性；取卵巢发育卵母细胞，测定细胞膜上卵黄生成素受体(VTGR)含量；取腺垂体样品，测定cAMP含量；取肝脏、输卵管子宫部组织，光镜、电镜观察其组织形态结构。 饲养试验表明：添加150mg／kg和300mg／kg二氢吡啶使蛋鸡平均产蛋率分别提高了9.39％(P＜0.01)和12.97％(P＜0.01)；料蛋比分别降低了9.54％(P＜0.05)和7.25％(P＜0.05)；对蛋重和日采食量无显著影响。 屠宰试验表明，添加150mg／kg和300mg／kg二氢吡啶使腹脂率分别下降了35.4％(P＞0.05)和46.9％(P＜0.05)。 肝脏和腹脂样品分析显示，日粮中添加150mg／kg和300mg／kg二氢吡啶，蛋鸡肝脂率分别降低32.4％(P＜0.05)和10.5％(P＜0.05)；腹脂HSL活性升高39.46％(P＜0.05)和48.48％(P＜0.05)。与对照组相比，150mg／kg二氢吡啶组肝脏apoB含量和SOD的活性分别提高了53.96％(p＜0.05)和69.61％(p＜0.01)，但300mg／kg二氢吡啶组肝脏apoB含量和SOD活性无显著变化。 肝组织显微观察可见，二氢吡啶组肝小叶中脂肪滴数量、体积明显下降(光镜)；添加二氢吡啶使肝脏贮脂细胞的数量和细胞内脂肪体积下降(电镜)；输卵管子宫部绒毛和蛋壳腺形态结构有明显改善(光镜)。 血清生化指标分析揭示，150Ing/kg、300mg/kg二氢毗陡使蛋鸡血清钙含量分别提高18.88%(P(0.01)、22.64%(P<0.01);使血清LDH活性分别降低26.40%(P<0.05)、54.76%(P<0.01);300 mg/kg二氢毗睫使蛋鸡血清中AST活性降低18.15%(P<O.05)，而150mg/kg二氢毗陡对蛋鸡血清中AST活性无显著影响;二氢毗睫对蛋鸡血清中甘油三脂、总胆固醇、HDL一C、vLDL一C、apoB、apoAI含量无显著影响。 血清激素测定结果表明，150m叭g和300m叭g二氢毗陡使蛋鸡血清T3水平分别升高了15.34%(P<0.05)和11.88(P<0.05);使血清胰岛素水平下降了40.44%(P<0 .01)和54.37%(P<0.01);但血清几水平未见显著变化。 cAMP含量测定结果表明，1 50m叭g、30om叭g二氢毗睫使蛋鸡腺垂体中cAMP分别提高了14.67%(P<0.05)、10.91%(P<0.05);但对肝脏中cAMP含量无显著影响。 肝细胞线粒体分析显示，15Omg/kg和300mg/kg二氢毗陡使线粒体MDA含量分别显著降低30.90%(P<0 .01)和10.39%(P<0 .05);使线粒体膜的荧光偏振度分别显著下降15.40%(P丈0.01)和7.56%(P<0 .05);使线粒体膜粘滞系数降低了25.05%(P<0.01)和13.10%(P<0 .05);线粒体膜各向异性显著下降16.36%(P<0 .01)和8.07%(P<0.05)，说明二氢毗咙能显著提高肝脏线粒体膜的流动性。 发育卵母细胞膜卵黄生成素受体(vTGR)分析表明，1 50mg/kg和300mg/kg二氢毗陡使卵黄生成素受体含量提高24.45%(P=0.13)和21.53%(P二0.14)，表明二氢毗陡有提高VTGR含量的趋势。更多还原

【Abstract】 The experiment was conducted to investigate the effects of 1,4-dihydropyridine (DHP) on Fatty Liver hemorrhagic Syndrome of laying hens and approach to the mechanism.Six hundreds of Laying hens of 40 weeks of age were randomly allotted to three groups, each of which included four replicates of 50 hens. The groups were fed a basal corn-soybean diet, supplemented 0(control);150mg/kg, 300 mg/kg 1,4-dihydropyridine. Feed and water were provided ad. Zibitum and layers received 16h light/day. 12 layers from each group were picked out after 90 days of feeding to collected samples of liver, abdominal fat, ovary, oviduct and anterior pituitary. Serum bio-parameters, levels of hormone, liver fat percentage, abdominal fat percentage, hormone sensitive lipase(HSL) activities in abdominal fat, liver superoxide simutase (SOD) activities and apolipoproteinA I and apolipoproteinB concentrations, cAMP concentrations in liver and anterior pituitary, MDA concentrations and P, r, values of liver mitochondria were determined to study the mechanism of effects.The results indicated that DHP had significantly improved laying performance. Adding 150mg/kg, 300mg/kg DHP to the diet improved daily mean laying rate by 9.39%(P<0.01), and 12.97%(P<0.01), decreased feed/egg ratio by 9.54%(P<0.05) and 7.25%(P<0.05) respectively. However, there were no significantly difference between treatments in egg weight and daily feed intake.The determination of abdominal fat and liver samples showed that DHP had significant effect on percentage of abdominal fat and liver fat. Supplementation of 150 mg/kg, 300mg/kg DPH decreased percentage of abdominal fat by 35.4%(P<0.05) and 46.9%(p<0.05),and decreased liver fat by 32.4%(p<0.05) and 10.5%(p<0.05) respectively.Adding 150mg/kg, 300mg/kg DHP to the diet increased HSL activity of abdominal fat by 39.64%(p<0.05) and 48.48%(p<0.05). The dieting addition of 150mg/kg DHP increased liver SOD activity by 69.61%(p<0.05), and increased liver apoB concentration by 53.96%(p<0.05), but a similar significant effect on liver SOD activity and apoB concentration.The results from serum biochemical parameters analysis indicated that supplementing 150mg/kg , 300mg/kg DHP increased calcium concentration by 18.88% (p<0.01)and 22.64%(p<0.01), decreased LDH activities by 26.40%(p<0.05) and 54.76%(p<0.01) respectively. Adding 300mg/kg DHP to the diet decreased AST activity by 18.15%(p<0.05), but 150mg/kg DHP not.The investigation of levels of hormone in serum showed that adding 150mg/kg , 300mg/kg DHP to the diet increased T3 levels by 15.34% (p<0.05) and 11.88%(p<0.05); decreased insulin concentration by 40.44%(p<0.05) and 54.37%(p<0.05) respectively; but no significant effect occurred on T4 concentration.The present result indicated that supplemented 150mg/kg, 300mg/kg DHP increased the concentrations of cAMP in anterior pituitary by 14.67%(p<0.05) and 10.91%(p<0.05) respectively, but a similarity significant difference was not found.The results from liver mitochondria indicated that supplementation of 150mg/kg , 300mg/kg DHP decreased MDA concentration by 30.90%(p<0.01) and 10.39%(p<0.05), the liver mitochondria! membrane polarization fluorescence degree (P) lowered by 15.40%(P<0.01) and 7.56%(P<0.05), decreased the anisotropy( r) by 25.05%(P<0.01) and 13.10%(P<0.05), lowered the exiguity viscosities( n ) by 16.36%(P<0.01) and 8.07%(P<0.05) respectively. This result suggested DHP increase mitochondria membrane fluidity.The research on very low density lipoprotein receptor(VLDLR) indicated that adding DHP had the tendency for VLDLR activities of ovarian to be higher.更多还原