【作者】 杜伟；

【导师】 王恬；

【作者基本信息】 南京农业大学 ， 动物营养与饲料科学， 2007， 硕士

【摘要】 为研究胰岛素及酪蛋白酶解物对新生IUGR(Intrauterine Growth Retardation，IUGR)仔猪肝脏生长发育的影响，试验比较了新生IUGR仔猪及人工饲喂牛乳、牛乳补加胰岛素、酪蛋白或酪蛋白酶解物三天后IUGR仔猪肝脏的重量，蛋白质、DNA和RNA含量，肝脏中肝糖原含量、超氧化物歧化酶活性、丙二醛含量、过氧化氢酶活性、谷胱甘肽过氧化物酶活性、肝酯酶活性、苹果酸脱氢酶活性以及血浆中游离脂肪酸含量、谷草转氨酶活性、谷丙转氨酶活性、超氧化物歧化酶活性、丙二醛含量、总胆固醇含量、甘油三酯含量、肝酯酶活性、胰岛素和IGF-I含量。试验一选择“苏太猪”初生仔猪5窝，每窝选择3头IUGR仔猪，分别分到新生组(A)、牛乳组(M)、牛乳补加胰岛素(60IU／L)组(I)。A组出生后立即宰杀，M组和I组人工饲喂3天，每3小时喂一次，饲喂量为每次30mL／kgBW，3天后屠宰取样，测定与肝脏生长发育相关的指标。与新生仔猪相比，人工饲喂三天后，仔猪体重无明显变化，但仔猪的肝脏重量显著升高(P＜0.05)，I组仔猪肝脏的蛋白质、DNA、RNA含量都有上升的趋势，但由于个体差异，变化不显著(P＞0.05)。M组和I组的肝糖原比A组略有下降，但血糖含量显著上升(P＜0.05)，脂代谢相关的酶变化剧烈，除血浆游离脂肪酸下降之外(P＜0.01)，血浆总胆固醇、甘油三酯和肝脏中苹果酸脱氢酶在饲喂三天后都极显著上升(P＞0.01)，I组血浆中肝酯酶含量高于其他两组，但差异不显著(P＞0.05)。M组、I组丙二醛含量下降(P＜0.05)，超氧化物歧化酶活性有明显上升(P＞0.05)，肝脏中过氧化氢酶和谷胱甘肽过氧化物酶活性显著上升(P＜0.05)，血浆中谷草、谷丙转氨酶也显著上升(P＜0.05)，但除了谷胱甘肽过氧化物酶外，M组和I组之间无显著差异(P＞0.05)。I组血浆胰岛素含量极显著高于A组，也极显著低于M组(P＜0.05)，IGF-I含量变化不大。结果表明，口饲胰岛素能刺激新生IUGR仔猪肝脏的生长发育及功能的成熟。试验二选择初生苏太猪5窝，每窝选择3头IUGR仔猪，分别分到新生组(A)、牛乳+酪蛋白组(C)和牛乳+酪蛋白酶解物组(CH)。A组仔猪出生后立即屠宰取样；C组和CH组分别用1.5％酪蛋白溶液和1.5％酪蛋白酶解液取代10％(v／v)的牛乳，人工饲喂3天后屠宰取样。添加酪蛋白酶解物的试验结果总体与添加胰岛素类似。试验发现，虽体重略有下降，但C组和CH组的仔猪肝脏重量均有大幅增加(P＞0.05)，CH组仔猪肝脏中DNA含量显著增加(P＜0.05)，蛋白质和RNA含量也有增加趋势(P＞0.05)。过氧化物歧化酶、过氧化氢酶和谷丙转氨酶活性CH组显著升高(P＜0.05)，丙二醛含量显著下降(P＜0.05)．人工饲喂三天后，血浆游离脂肪酸水平显著下降，肝脏内苹果酸脱氢酶活性和血浆中甘油三脂含量显著上升(P＜0.05)，而总胆固醇和肝酯酶活性无显著变化(P＞0.05)．血浆中的IGF-I和胰岛素含量三个试验组无显著差异。试验表明，酪蛋白及酪蛋白酶解物可以促进IUGR仔猪肝脏的生长发育，提高肝脏的抗氧化能力，增强糖脂代谢能力。更多还原

【Abstract】 In order to investigate the effects of insulin and casein hydrolysate on the growth and development of liver in intrauterine growth retardation (IUGR) piglets, the experiment compared the difference of liver weight, content of protein, DNA and RNA, activities of superoxide dismutase(SOD), hepatic lipase(LP), glutamine-oxaloacetic transaminase(GOT), glutamic-pyruvic transaminase(GPT), contents of free fatty acid(FFA), malonddialdehyde (MDA), total cholesterol(TC), triglyceride (TG), insulin, insulin-growth factor I(IGF-I) in plasma and activities of SOD, HL, catalase(CAT), glutathione peroxidase(GSH-Px), malate dehydrogenase(MDH), contents of glycogen, MDA in liver among newborn piglets, piglets bottle-fed for 3 days with cow-milk and cow milk supplemented with insulin, casein or casein hydrolysate.In the first experiment, fifteen Sutai IUGR piglets were selected from five litters, three piglets from every litter, and divided into three groups: newborn group(N), milk group(M) and milk supplemented with insulin (60IU/L) group(I), five IUGR piglets in every group. Compared with group A, liver weight and glycose in plasma of IUGR piglets bottle-fed for 3 days was increased significantly(P<0.05), the content of protein, DNA and RNA was increased (P<0.05). The content of TG, TC, MDH was significant increasedtotal proteolytic activity of protease in stomach but total milk-clotting activity of gastric protease was decreased(P<0.01), while FFA in plasma was decreased(P<0.01). Content of MDA of IUGR piglets in group I was decreased and the activities of SOD, GSH-Px, CAT, GOT, GPT was increased significant(P<0.05). The content of insulin in plasma of IUGR piglets bottle-fed for 3 days was in a high level(P<0.01).The results show that oral insulin can stimulate the growth of liver of the IUGR piglets and the maturity of function.In the second experiment, fifteen Sutai piglets were selected from five litters, three IUGR piglets from every litter, and allotted to three groups: newborn group(A), casein group(C) and casein hydrolysate group(CH), five IUGR piglets in every group. The piglets in group C and CH were fed milk substituted 1.5% casein and 1.5% hydrolysed casein solution for 10% (v/v) milk for 3 days. After the piglets were fed artificially for 3 days, the result showed in this experiment is similar to experiment one. Although the body weight was decreased, the liver weight of group C and group CH was increased quickly ( P>0.05 ), while the content of DNA in the liver in IUGR piglets of group CH was increased significantly (P<0.05) , and the content of RNA and protein was increased rapidly at the same time (P>0.05) . The activities of SOD, CAT and GPT were increased obviously ( P<0.05 ), in contrast, the content of MDA decreased (P<0.05). After the piglets were fed manually for 3 days, the level of FEA in plasma was decreased significantly, and the level of the MDH in the liver and the TG in plasma was risen up (P<0.05 ), but the level of TC and HL kept alike. The content of IGF-I and insulin in three groups had no significant changes ( P>0.05 ). The data indicated that the casein and casein hydrolysate could promote the growth and development of the liver in IUGR piglets, also they could enhance the capability of the antioxidant and the metabolism of glycose and grease in the liver of IUGR piglets.更多还原