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小肽的营养功能及在畜牧业生产中的应用 总被引：1，自引：0，他引：1
近年来的研究改变了长期以来人们对蛋白质营养理论的认识,蛋白质营养已经不是简单的氨基酸营养,小肽营养也占据了非常重要的地位。肽是蛋白质的消化产物,氨基酸残基数目低于50个称为多肽,2～10个氨基酸组成的称之为寡肽,寡肽中含有2或3个氨基酸残基的为小肽。小肽可被完整地吸收进入动物循环系统．直接被组织代谢利用．在动物营养与代谢中起到重要作用。 相似文献
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传统的经典蛋白质营养理论即氨基酸营养理论认为,动物采食的日粮蛋白质在消化道内经蛋白酶和肽酶作用降解为小肽和游离氨基酸,游离氨基酸可被动物直接利用,而小肽只有进一步降解为游离氨基酸才能被利用。但在后来的一些研究中发现,用纯合日粮或低蛋白质平衡氨基酸日粮饲喂动物,并不能达到最佳生产性能。Agao等(1953)首先观察到肠道能完整地吸收转运双甘肽。Neway等(1960)的研究为小肽能被完整吸收提供了证据。Hara等(1984)在小肠黏膜上发现了小肽载体。Garder(1984)研究也表明,大量小肽能直接被吸收,进入体循环。Webba(1989)研究表明,蛋白… 相似文献
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传统的蛋白质营养理论认为,蛋白质在肠道中都被消化成氨基酸,然后通过肠壁被机体吸收,蛋白质营养就成了氨基酸营养。事实上,许多试验表明,用纯化组合日粮或低蛋白质平衡氨基酸日粮饲喂动物,并不能使其表现出最佳生产性能。随着研究的深入开展,产生了一些蛋白质营养的新认识和新观点,其中最为重要的应是小肽营养的理论,已逐渐被接受,蛋白质营养包括氨基酸营养和小肽营养。当蛋白质以小肽形式供给时,可提高动物对蛋白质的利用率,进一步发挥动物的生产潜能,具有增强动物免疫、防病抗病能力、改善动物产品品质等重要作用。对于反刍动物的蛋白质… 相似文献
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蛋白质在动物营养中起着重要作用,大量研究已表明蛋白质营养不仅是游离氨基酸营养,肽营养也具有重要作用。本文综述了反刍动物肽的吸收特点及影响因素,肽的吸收代谢机制,肽对瘤胃微生物的调控及对反刍动物生产性能发挥的作用,并阐述饲料蛋白源活性肽的开发应用及肽营养研究与应用前景。 相似文献
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小肽在动物营养中的作用及研究趋势 总被引：1，自引：0，他引：1
小肽是动物降解蛋白质为氨基酸过程中的中间产物,是一种重要的营养素,它能被动物体直接吸收的肽营养理论是动物营养学上的一个重要发现,是对传统蛋白质营养理论的丰富和完善,它在蛋白质的消化、吸收和代谢中起重要作用。文中重点从小肽的吸收机制、营养功能和研究趋势等方面进行综述。 相似文献
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Use of a systems approach, as embodied in the computer simulation model of metabolism of a dairy cow, Molly (Baldwin, 2005), is ideal for teaching nutrition. This approach allows the overall complexity of the comprehensive system to be broken down into smaller manageable subunits that are easier to visualize. Quantitative interactions among nutrients supplied and metabolic production processes can be observed over extended time periods. Using Molly, undergraduate animal science students are able to observe detailed effects of changing dietary inputs, altering genetic milk production potential, and exogenously manipulating metabolism on metabolism of the whole cow. This paper demonstrates how Molly is used in the classroom to teach a systems approach to nutrition using example simulations. Three simulation examples demonstrate exercises examining effects of recombinant bovine somatotropin administration, dietary protein, and amino acid supplementation and nitrogen efficiency on milk production and cow metabolism. These and similar examples have been used to teach nutrition, metabolism, and lactation to undergraduate students for the past 20 yr. 相似文献
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Mao NAGASAWA Tatsuro MURAKAMI Mikako SATO Yoshihisa TAKAHATA Fumiki MORIMATSU Mitsuhiro FURUSE 《Animal Science Journal》2012,83(6):493-498
Several amino acids have effects on mental function, including sedative, antidepressant‐like and anxiolytic‐like effects. However, the influence of integrated amino acid nutrition as protein constituents on mental function remains unclear. Therefore, the purpose of the present study was to compare the influence of chicken, pork and beef protein extracts on brain monoamine metabolism in mice. Changes in monoamine levels and their turnover rates in the brain were induced by different protein sources. In particular, chicken protein group showed the highest norepinephrine levels in the hippocampus and hypothalamus, and beef protein extract caused an activation of the serotonergic system in the hypothalamus, although there were no significant differences in amino acid compositions of these protein extracts. Therefore, it was revealed that amino acid compositions in dietary protein did not induce alteration in monoamine metabolism. However, there were differences in small molecular peptides, such as creatine, carnosine and anserine levels in animal protein extracts. In conclusion, monoamine metabolism was altered by dietary protein sources. However, it was indicated that the alteration in monoamine metabolism may be independent from amino acid compositions in dietary protein. In addition, alteration in monoamine metabolism depending on the dietary protein sources may be induced by small molecular peptides. 相似文献
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蛋白质是动物的必需营养素,对单胃动物而言,蛋白质营养实质上是氨基酸(小肽)营养;反刍动物由于具有瘤胃特殊消化生理结构和微生物消化方式,蛋白质营养更加复杂。蛋白质营养价值的评定方法是研究动物蛋白质营养的基础和前提,针对反刍动物消化生理特点,综述了尼龙袋技术、微生物标记技术、同位素法、嘌呤衍生物法和人工瘤胃等反刍动物蛋白质营养价值评定方法,这对于理论研究和实践生产具有一定参考与指导作用。 相似文献
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Effects of gastrointestinal nematode infection on metabolism and nutrient utilisation in sheep are reviewed. Infection induces protein deficiency by increasing the demand for amino acids in the alimentary tract while reducing supply through depression of appetite. Mechanisms through which improved protein nutrition could improve the performance of the host are then discussed. Opportunities for capitalising on such effects are limited by our rudimentary understanding of the cell-mediated immune response in gastrointestinal epithelial tissue. Both resistance of the animal to larval establishment and performance in the face of larval challenge can be enhanced by improved protein nutrition. However, enhanced immune responses may not necessarily be synonymous with improved productivity except at luxurious levels of protein intake, because of apparently competing demands for protein. Such levels of protein nutrition are difficult to achieve in pasture-based systems, because of the protein limiting role of the rumen. Work with protein-protecting tannins to overcome this limitation is discussed. The much more limited evidence for effect of mineral nutrition, particularly copper (Cu), molybdenum (Mo), cobalt (Co) and phosphorus (P), on outcome of larval challenge is also reviewed. 相似文献