【作者】 苏鹏程；

【导师】 卢德勋；

【作者基本信息】 内蒙古农业大学 ， 动物营养与饲料科学， 2004， 博士

【摘要】 本文采用“灌注营养技术”、“慢性血插管技术”、“稳定性同位素示踪技术”和“比较屠宰试验技术”等先进技术手段和方法，对不同代谢葡萄糖水平日粮条件下，内蒙古白绒山羊体内蛋白质（氨基酸）分配规律进行了系统研究。首先，测定在1.2M基础日粮条件下绒山羊瘤胃丙酸产量、过瘤胃淀粉量和MCP产量等，进而计算基础日粮的MG、MP值，同时对小肠氨基酸消化流通规律进行研究。然后，在理想氨基酸模式（M85+C15）下，设定三个代谢葡萄糖水平，采用“慢性血插管技术”，结合消化试验，从消化道和组织代谢不同层次入手，研究不同代谢葡萄糖水平日粮条件下动物组织氨基酸利用的变化情况，以揭示不同代谢葡萄糖水平日粮条件下绒山羊氨基酸利用的规律和机理。最后采用“稳定性同位素示踪技术”和“比较屠宰试验技术”等，在产绒旺盛期，研究在相同理想氨基酸模式、不同代谢葡萄糖水平日粮条件下，蛋白质（氨基酸）在绒山羊机体不同组织的分配情况，进而揭示蛋白质（氨基酸）在不同组织的分配规律。该项研究结果发现代谢葡萄糖水平影响白绒山羊体内蛋白质（氨基酸）的代谢与分配；代谢葡萄糖与小肠理想氨基酸模式下的代谢蛋白质之间存在适宜的比值，生绒适宜的MG/MP为1.06，整体适宜的MG/MP为1.64。第一部分 基础日粮MG、MP的测定及白绒山羊小肠氨基酸消化流通规律的研究试验1：基础日粮条件下白绒山羊瘤胃丙酸产量及吸收规律的研究本试验选用3只体况良好，2岁内蒙古白绒山羊半同胞羯羊，体重20～23kg，安装有永久性瘤胃瘘管进行试验。试验采用间接测定法，研究瘤胃丙酸产量及吸收率。结果表明，在连续饲喂基础日粮条件下，瘤胃丙酸灌注前与灌注后的产生速率分别为5.53mmol/h和9.80mmol/h；外流速率分别为2.57mmol/h和4.96mmol/h；吸收速率分别为2.96mmol/h和4.84mmol/h；吸收率分别为52.94%和49.21%。 试验2：基础日粮条件下绒山羊过瘤胃淀粉产量、淀粉小肠消化率的研究本试验选用3只体况良好，安装有永久性瘤胃瘘管、十二指肠瘘管和回肠瘘管、体重20～23kg的2岁内蒙古白绒山羊半同胞羯羊进行试验。试验以Co-EDTA为食糜标记物，采用体内法测定过瘤胃淀粉产量、淀粉小肠消化率，结果表明，在饲喂基础日粮的条件下，绒山羊十二指肠淀粉流通量为59.50克。 淀粉在胃区中的消失率为58.23%，在小肠、大肠和整个消化道<WP=3>的表观消化率分别为54.47%、5.55%和82.05%。试验3：基础日粮条件下白绒山羊十二指肠氨基酸流通量、消化率及微生物蛋白（MCP）产量的研究选用3只体况良好，体重23～25kg的2岁内蒙古白绒山羊半同胞羯羊，安装永久性瘤胃瘘管，十二指肠近端瘘管和回肠末端瘘管进行试验。试验采用体内法，实测内蒙古白绒山羊小肠氨基酸表观消化率,并对氨基酸平衡性进行评定。结果表明：在基础日粮条件下，小肠总氨基酸、必需氨基酸、非必需氨基酸的表观消化率分别为： 68.41%， 68.68%和68.11%。在所有氨基酸中，赖氨酸的消化率最高，为74.77%，半胱氨酸的最低，为52.72%。小肠可吸收氨基酸平衡指数为0.69。十二指肠的微生物蛋白氮流量为1.93g/d。试验4：基础日粮MG和MP的测定 根据试验1、试验2和试验3试验结果的计算表明，在1.2M饲养水平下，基础日粮提供的POEG值为6.40g/d，BSEG值29.16g/d，MG为35.56g/d；基础日粮提供的MP值为 27.62g/d。第二部分 不同MG水平日粮对绒山羊小肠氨基酸消化、吸收和代谢影响的研究试验1：不同日粮MG水平对绒山羊小肠氨基酸消化和吸收影响的研究本试验采用随机区组试验设计，选用9只体况良好，体重20～23kg的2岁安装有永久性瘤胃瘘管、十二指肠瘘管和回肠瘘管的内蒙古白绒山羊半同胞羯羊进行试验。三个组试验羊灌注相同氨基酸，不同水平的葡萄糖，使进入绒山羊十二指肠的各种氨基酸（日粮氨基酸+灌注氨基酸）达到M85+C15（即85%的肌肉和15%的绒毛）的理想氨基酸模式，1、2、3组的代谢葡萄糖水平分别为35.56g/d、55.56g/d和70.56g/d。结果表明，本试验条件下，随MG水平的提高，非必需氨基酸，必需氨基酸中Lys、Arg、Ilu、Val、Phe的表观消化率降低，2、3组明显低于1组（P＜0.05）。2、3组之间差异不显著（P＞0.05）。试验2：不同MG水平日粮下PDV组织及肝脏对氨基酸利用规律的研究本试验选用3只体况良好，体重23～25kg的2周岁内蒙古白绒山羊半同胞羯羊，安装永久性十二指肠近端瘘管以及门静脉、肠系膜静脉、肝静脉、股动脉慢性血插管进行试验。试验采用3×3拉丁方试验设计，3个试验处理组分别为M85+C15理想氨基酸模式条件下的3种MG水平，MG分别为35.56g/d、55.56g/d和70.56g/d 。结果表明，日粮MG水平对肝脏血浆非<WP=4>必需氨基酸净流量有显著影响，2、3组显著高于1组(P<0.05) ，2、3组之间差异不显著（P＞0.05）。对MDV、PDV组织血浆总氨基酸、必需氨基酸、非必需氨基酸净流量无显著影响（P＞0.05）。说明随MG水平的提高，非必需氨基酸用于葡萄糖异生的量减少。第三部分 不同日粮MG水平对绒山羊体内蛋白质、氨基酸分配影响规律的研究试验1：不同日粮MG水平对绒山羊氮代谢影响的研究 本试验采用随机区组试验设计，选用9只体况良好，体?更多还原

【Abstract】 This paper mainly studied on partitioning of proteins (amino acids) in Inner Mongolian White Cashmere (IMWC) goats fed diets with different dietary metabolizable glucose (MG) Levels by nutrients infusion technique, arterio- venous technique, isotope technique and comparative slaughter technique. Firstly, It was determinated that amount of ruminal propionate yield, bypass starch and ruminal microbial protein (MCP) in IMWC goats in vivo. Then the values of dietary MG and metabolizable protein (MP) in basal diets were calculated. It was studied also that the amino acid flow into the duodenum and the digestibility of amino acids in the small intestine of IMWC goats fed the basal diets. Secondly, Three dietary MG levels with the same M85+C15 ideal absorbable amino acid pattern were designed to investigated the effect of dietary MG level on metabolism and utilization of amino acids in IMWC goats by arterio- venous catheter technique and digestion trials, so as to find the rule and mechanism of amino acids utilized by IMWC goats at different dietary MG Level. Finally, The partitioning of proteins (amino acids) in IMWC goats at different MG levels were studied by isotope technique and comparative slaughter technique, so as to find the rule of the partitioning of proteins (amino acids) in IMWC goats. The results showed that dietary MG levels could have a great impact on the metabolism and partitioning of amino acids in IMWC goats, and it was also suggested that there was an proper ratio between MG and MP, the proper MG/MP ratio was about 1.06 for cashmere production and 1.64 for whole body.Part 1 Determination of values of MG and MP in basal diet and study on amino acid flow and digestion in the small intestine of IMWC goats fed the basal diet Exp.1 Determination of the propionate yield and absorption rate in the rumen of IMWC goats fed the basal diet by in vivo technique Three wethers of IMWC goats (20-23kg) with the same father, fitted with permanent cannulas in the rumen were used to determinate the propionate yield and absorption rate in the rumen and fed the basal diet by in vivo technique. The results showed the propionate yield, outflow rates, absorption rate and absorptivity were 5.53mmol/h, 2.57 mmol/h, 2.96 mmol/h and 452.94%, respectively. Before infusion of propionate, and 9.80 mmol/h 4.96 mmol/h, 4.84 mmol/h and 49.21% respectively after infusion of propionate .Exp.2 Determination of the quantities and the digestibility of bypass starch in the small intestine of the growing goats fed the basal dietsThree wethers of IMWC goats (20-23kg) with the same father were used to investigate the quantities and digestibility of bypass starch of the diets in the small intestine in vivo. The results indicated that the quantities of bypass starch of the basal diets were 59.50g/d; the disappear proportion of starch in the rumen <WP=7>was 54.47 %, the digestibility of bypass starch in the small intestine was 58.23%, was 5.55% in large intestine and 82.05% in whole intestine, respectively.Exp.3 Study on amino acid flows and digestion in the small intestine and ruminal MCP production of IMWC goats fed the basal diet Three wethers of IMWC goats (20-23kg) with the same father fitted with permanent cannulas in the rumen, at the proximal duodenum and terminal ileum were used to investigate amino acid flows and digestibility in different sites of the digestive tract and ruminal MCP production of IMWC goats fed the basal diet. The results showed the average apparent digestibility of TAA, EAA and NEAA in the small intestine was 68.41%, 68.68% and 68.11%, respectively. The average apparent digestibility of Lys was 74.77% being the highest in TAA, the average apparent digestibility of Cys was 52.72%, being the lowest in TAA. The balance index of absorbable amino acid in the duodenum was 0.69.The flow of nitrogen of MCP into the duodenum was 1.93g/d.Exp.4 Determination of MG value of the dietsAccording to the results of Exp.1, Exp.2 and Exp.3, the dietary POEG, BSEG and MG were calculated as 6.40 g/d, 29.16 g/d and 35.56更多还原