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我国对猪可消化氨基酸的研究起步较晚,但也取得了巨大成就,测定了猪常用饲料原料的氨基酸消化率,确定了可消化氨基酸需要量与平衡模式并逐步在畜牧业生产中得到应用[1]. 相似文献
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猪禽饲料氨基酸消化率测定研究进展 总被引:7,自引:1,他引:6
猪禽饲料氨基酸消化率测定研究进展西北农业大学姚军虎四川农业大学王康宁·营养研究·饲料氨基酸(AA)消化率的测定是评定猪禽饲料蛋白质营养价值的一个重要方面。自Kuiken等(1948)首先用粪分析法测定猪饲料氨基酸消化率以来,单胃动物氨基酸消化率的测定... 相似文献
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目前许多饲料厂家用总氨基酸含量设制日粮配方。因为氨基酸尤其是几种限制性氨基酸的消化率差异大,用总氨基酸含量配制日粮可能过高或过低估计了氨基酸的营养价值,导致氨基酸营养不平衡。许多研究认为,用可消化氨基酸配制日粮比总氨基酸日粮更精确,在选用氨基酸含量低或消化率变异大的饲料原料时更是如此。用可消化氨基酸配制日粮可以更准确地预测猪的生产性能并降低生产成本。 1氨基酸消化率的测定方法 现在已普遍用回肠分析法测定猪饲料氨基酸消化率,粪分析法较少采用。在过去二十年间曾测定了许多种饲料的猪回肠表观氨基… 相似文献
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关于按可利用氨基酸设计猪饲料配方的初步建议 总被引:2,自引:0,他引:2
《中国饲料》1996年第5期刊出“关于按可利用氨基酸设计家禽饲料配方的初步建议”后,一些读者来信询问设计猪饲料配方的有关资料。今将这方面的资料综合撰文于下。与家禽一样,这只是一个初步建议,目的是抛砖引玉。为猪设计以可利用氨基酸为指标的饲料配方,同样需要有饲料中可利用氨基酸含量和猪的可利用氨基酸需要量等基础数据。1猪饲料的可利用氨基酸含量猪对饲料中氨基酸的利用率,目前大多用回肠末端表观消化率表示。国内外许多学者发表了这方面的测定数据。由于基因型、生产条件以及测定方法等因素的影响,同名饲料由不同学者测得的… 相似文献
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Heger J Van Phung T Krizová L 《Journal of animal physiology and animal nutrition》2002,86(5-6):153-165
A series of N balance experiments using growing pigs was conducted to study the efficiency of utilization of lysine, threonine, sulphur amino acids and tryptophan and to estimate their maintenance requirements. Purified diets based on casein and crystalline amino acids as the sole source of N contained graded levels of each amino acid, corresponding to expected protein accretion rate of 0, 33, 66, 99 and 132 g/day, respectively. N retention increased linearly (p < 0.01) as the dietary concentration of the limiting amino acid increased. Based on linear regression equations relating amino acid deposition in body protein to amino acid intake, marginal efficiencies of ileal digestible amino acid utilization were calculated to be lysine 0.91, threonine 0.83, sulphur amino acids 0.85 and tryptophan 0.66. Extrapolating the regression equations to zero N retention, the daily requirements of amino acids for N equilibrium were estimated to be (mg/kg(0.75)) lysine 39, threonine 49, sulphur amino acids 46 and tryptophan 16. 相似文献
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研究反刍动物氨基酸需要量的最常用方法为屠体氨基酸分析法和真胃或十二指肠灌注法 ,研究者们采用不同的方法研究了肉牛的氨基酸需要量。在生长肉牛的实用日粮条件下 ,蛋氨酸或赖氨酸常为第 1限制性氨基酸 相似文献
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This article describes the National Research Council Model of protein metabolism and illustrates its use in meeting the protein requirements of lactating cows. Attention is then directed toward amino acid nutrition with emphasis on the need for models to estimate amino acid requirements. Finally, the potential to improve productivity with rumen-protected amino acids is considered. 相似文献
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Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation. A deficient AA supply results in a reduction in performance while an oversupply is costly and leads to excessive nitrogen excretion with a potentially negative environmental impact. Amino acid requirements are determined to a large extent by the protein deposition in the body and, for lactating sows, by the protein exported in the milk. The concept of ideal protein was developed more than 50 years ago and refers to a protein with an amino acid profile that exactly meets the animal’s requirement so that all amino acids are equally limiting for performance. Because Lys typically is the first-limiting amino acid, the ideal amino acid profile is often expressed relative to Lys. Although the ideal protein profile is often assumed to be constant for a given production stage, (small) changes in the ideal protein profile can occur within a production stage. This can be caused by changes in the relative contribution of the different components of amino acid requirements during the productive life on the animal (e.g. changes in the relative contribution of growth and maintenance). Amino acids requirements can be determined experimentally using dose–response studies. The design of the study, the chosen response criterion, and the statistical model affect the requirement estimate. Although considerable experimental work has been carried out to determine the requirements for Lys, Met, Thr, and Trp in growing pigs (and to a lesser extent in sows), little is known about the requirements for the other essential amino acids. Experimental dose–response studies generally focus on the requirement and less on the overall response (i.e. what are the consequences of an amino acid deficiency?). This latter aspect is, to some extent, accounted for in modelling approaches that quantify the response of the animal to the amino acid supply in a dynamic way. The paper describes the origin of ideal protein and illustrates how fundamental concepts of amino acid nutrition have been integrated in practical modeling approaches for the nutrition of growing pigs and sows. 相似文献
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《畜牧与生物技术杂志(英文版)》2015,(3)
Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation.A deficient AA supply results in a reduction in performance while an oversupply is costly and leads to excessive nitrogen excretion with a potentially negative environmental impact.Amino acid requirements are determined to a large extent by the protein deposition in the body and,for lactating sows,by the protein exported in the milk.The concept of ideal protein was developed more than 50 years ago and refers to a protein with an amino acid profile that exactly meets the animal's requirement so that all amino acids are equally limiting for performance.Because Lys typically is the first-limiting amino acid,the ideal amino acid profile is often expressed relative to Lys.Although the ideal protein profile is often assumed to be constant for a given production stage,(small) changes in the ideal protein profile can occur within a production stage.This can be caused by changes in the relative contribution of the different components of amino acid requirements during the productive life on the animal(e.g.changes in the relative contribution of growth and maintenance).Amino acids requirements can be determined experimentally using dose-response studies.The design of the study,the chosen response criterion,and the statistical model affect the requirement estimate.Although considerable experimental work has been carried out to determine the requirements for Lys,Met,Thr,and Trp in growing pigs(and to a lesser extent in sows),little is known about the requirements for the other essential amino acids.Experimental dose-response studies generally focus on the requirement and less on the overall response(i.e.what are the consequences of an amino acid deficiency?).This latter aspect is,to some extent,accounted for in modelling approaches that quantify the response of the animal to the amino acid supply in a dynamic way.The paper describes the origin of ideal protein and illustrates how fundamental concepts of amino acid nutrition have been integrated in practical modeling approaches for the nutrition of growing pigs and sows. 相似文献
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The consumption of poultry meats exceeds 50% of total meat consumption. With the outbreak of bovine spongiform encephalopathy and foot and mouth disease, the consumption of poultry meat is set to increase. The use of meat bone meal derived from cattle and pigs is prohibited. Therefore, plant protein has to be used more frequently and the importance of the study of amino acid nutrition is increasing. In order to improve dietary efficiency, it is necessary to elucidate the exact amino acid requirements of poultry. The amino acid requirements are not constant and are affected by various factors. By using the plasma amino acid concentration as a parameter, it is possible to predict the amino acid requirements within a short period using a small number of animals repeatedly. By satisfying the amino acid requirements through supplementing crystalline amino acids, it is possible to reduce dietary protein and excretory nitrogen simultaneously. However, when the dietary protein is reduced, the abdominal fat tends to increase. This is solved by deciding the optimum dietary protein level, but it is difficult to control the taste of poultry meat by dietary amino acids. 相似文献
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乳蛋白是体现牛奶质量的重要指标,乳蛋白氨基酸来源于日粮氨基酸。乳蛋白中酪蛋白、乳白蛋白和乳球蛋白除了满足人体基本营养需求,还对人体生长、发育和健康发挥重要作用,是动物源优质蛋白质来源。蛋氨酸与赖氨酸是奶牛日粮限制性氨基酸,不仅是乳蛋白合成的重要底物,同时还作为信号分子调控乳蛋白基因表达。本文综述了奶牛氨基酸需要与来源、必需氨基酸、限制性氨基酸、保护性蛋氨酸和赖氨酸在日粮中的应用,阐述了氨基酸营养在蛋白质合成代谢中的核心作用,为指导奶牛日粮配方提供参考。 相似文献
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In dairy cows amino acids may be required for four processes: maintenance; as precursors for the synthesis of glucose (gluconeogenesis); for protein deposition in muscle or associated with foetal growth; and for the synthesis of milk protein.Estimates of the protein requirements for maintenance are often conflicting and seem far from accurate. Estimates of the ratio in which essential amino acids are required for maintenance are not yet available.Requirements of amino acids for gluconeogenesis are difficult to estimate. It seems rather unlikely that essential amino acids will be used in significant quantities for gluconeogenesis, even at high milk yields.Protein requirements for pregnancy and muscle growth in dairy cows are relatively low. The ratio in which essential amino acids are supplied in the blood seems adequate for both processes.Amino acid requirements for milk protein synthesis are somewhat higher than the net protein output. This is particularly true for essential amino acids of which, in the mammary gland, a surplus of some 50% needs to be extracted from the blood. The ratio in which essential amino acids are supplied to the mammary gland seems reasonably adequate for milk protein synthesis. 相似文献
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利用氨基酸自动分析仪对从桑蚕丝条吐精炼液中回收的丝胶蛋白的氨基酸组成进行分析,采用聚丙烯凝胶电泳法对其相对分子质量进行测定,利用紫外分光光度计对其溶解性进行探究。结果表明:丝胶蛋白含有18种氨基酸,其中极性氨基酸占80.39%,丝氨酸占27.52%,天门冬氨酸占15.91%,苏氨酸7.41%;丝胶蛋白的相对分子质量集中分布于17~75 KD;丝胶蛋白溶解性优于大豆分离蛋白。 相似文献