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作者把以提高反刍动物对日粮营养物质的利用率和减少对环境污染为目标的一整套实用的营养技术称之为反刍动物绿色营养技术。本文从提高氮代谢利用率、提高日粮能量利用率和提高日粮矿物质利用率三个方面介绍了国际上在这些方面的研究进展和技术进步,并着重介绍了内蒙古畜牧科学院近年来在发展反刍动物绿色营养技术方面所取得的研究成果。本文介绍的反刍动物绿色营养技术措施有以下9种:(1)饲料蛋白质保护和尿素缓释技术;(2)激素调控氮代谢技术;(3)进入小肠食糜氨基酸平衡技术;(4)降低甲烷发散技术;(5)日粮营养平衡调控技术(利用代谢葡萄糖调控组织代谢层次C_3 C_6能占ME摄入量比值技术);(6)提高低质粗饲料的营养工程技术;(7)使用矿物质螯合物或络合物技术;(8)日粮阴阳离子平衡技术;(9)降低磷排放技术。作者着重指出,在设计和使用这些技术时,应强调围绕一定的调控目标,将多种营养技术措施加以系统组合,充分利用其正组合效应,尽量控制或缩小负组合效应,以达到充分发挥各种技术措施整体优势的目的。 相似文献
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随着反刍动物新蛋白质体系的提出,氨基酸营养研究随之进入崭新的局面。尤其是针对蛋白质、限制性氨基酸和肽的代谢,合理搭配日粮氨基酸,以及提高饲料蛋白质消化率和氮利用率成为反刍动物营养研究领域的新热点。本文综述了反刍动物瘤胃微生物在不同日粮条件下的氨基酸限制性顺序,限制性氨基酸的研究方法,理想的氨基酸模式,蛋氨酸与赖氨酸的代谢机理,以及限制性氨基酸代谢的影响因素,旨在为揭示反刍家畜瘤胃微生物限制性氨基酸代谢机理,建立调控反刍家畜氨基酸高效利用的营养技术方案提供理论依据和技术支持。 相似文献
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通过对围产期与泌乳早期奶牛营养代谢特征及其与生产性能,繁殖率和健康关系的分析,作者提出改善能量负平衡,调整日粮营养组分,补充维生素和矿物质等营养调控手段,是降低奶牛代谢病发生率,改善繁殖性能,提高生产性能的有效策略. 相似文献
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在反刍动物饲料中精粗比是一个很重要的问题．精粗比例不当会引起很多问题。通过阐述精粗比对反刍动物消化代谢等方面的影响，旨在使养殖生产者了解瘤胃酸中毒的发生原因及饲喂精料过多所造成的危害，能充分重视日粮供应和精粗比例．避免饲料浪费和牛酮病的发生，为提高反刍动物饲料利用率的营养调控技术提供参数．并为合理调制日粮提供理论依据。 相似文献
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反刍动物乳腺是一个很活泼的蛋白质合成场所,90%以上的乳蛋白都是在乳腺中合成,其合成过程与其他组织合成蛋白质的过程相似。乳腺也是主要的氨基酸代谢调控组织,氨基酸抽取和转化为乳蛋白的机理与乳的分泌有关。血流量是主要的调控点,血液的流动可以改变乳腺的营养供给和平衡。因此,有必要对组织内氨基酸营养代谢尤其是泌乳反刍动物乳腺内氨基酸营养代谢进行深入研究,以便能准确地预测日粮中可利用蛋白质对乳蛋白的影响,使奶牛生产者能更好地配制日粮,提高日粮蛋白质的转换效率,同时为确定提高乳蛋白含量的方法和措施提供理论依据。1乳腺对… 相似文献
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Advances in Enhancing Nutrient Utilization for Ruminants by Nutritional Manipulation to Reduce Environmental Contamination 《畜牧与饲料科学》2010,31(6):386-386
A review of present understanding of the dietary nutrient utilization in ruminant animals is presented.For increasing the utilization of dietary nutrients and reducing environmental contamination,highlighting the development and use of nutritional manipulation technique is suggested. 相似文献
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Sources of variation and prospects for improvement of productive efficiency in the dairy cow: a review 总被引：4，自引：0，他引：4
D E Bauman S N McCutcheon W D Steinhour P J Eppard S J Sechen 《Journal of animal science》1985,60(2):583-592
In this review, "productive efficiency" in dairy cows is defined as the yield of milk obtained in ratio to the nutritional costs associated with maintenance, milk synthesis and loss of body condition during lactation. Improvements in efficiency could occur as a result of changes in digestion and nutrient absorption, maintenance requirement, utilization of metabolizable energy for production or nutrient partitioning. Digestibility can be greatly enhanced by appropriate dietary manipulation. Likewise, it may be possible to reduce maintenance requirements and improve the efficiency with which metabolizable energy is used for milk synthesis by manipulation of the pattern of nutrients presented to tissues. However, these factors apparently do not respond to selection for increased milk yield, and little variation is observed among cows. In contrast, individual cows differ substantially in feed intake and in the partitioning of nutrients among body tissues. Techniques associated with genetic engineering and the early prediction of genetic merit have the potential to improve productive efficiency by manipulation of these processes. However, changes in nutrient partitioning and feed intake during lactation are coordinated by a complex network of controls that accommodate the nutrient requirements of each tissue while maintaining homeostatic balance. Future improvements in productive efficiency will therefore depend on our ability to understand the manner in which these controls operate. 相似文献
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日粮纤维目前基本认定为第七大营养素,在猪体内中虽然消化率不高,甚至会影响其他营养素消化吸收,但能发酵产生短链脂肪酸,具有改善肠道微生物环境、调控母猪生理行为、调控猪肠道健康等作用。文章综述了日粮纤维在猪体内的营养特性和对肠道的调控作用,为日粮纤维在猪生产中的应用提供参考。 相似文献
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Nutritional strategies for managing the heat-stressed dairy cow 总被引：1，自引：0，他引：1
West JW 《Journal of animal science》1999,77(Z2):21-35
Heat stress results from the animal's inability to dissipate sufficient heat to maintain homeothermy. Environmental factors, including ambient temperature, radiant energy, relative humidity, and metabolic heat associated with maintenance and productive processes, contribute to heat stress. The focus of this article is to identify environmental and metabolic factors that contribute to excessive heat load, describe how disruption of homeothermy alters physiologic systems of the cow, and discuss nutritional modifications that help to maintain homeostasis or prevent nutrient deficiencies that result from heat stress. Changes in diet are needed during hot weather to maintain nutrient intake, increase dietary nutrient density, or to reestablish homeostasis. Formulation for adequate nutrient intake is challenging because of the competition between nutrient density and other needs for the cow, including energy density and adequate dietary fiber. Lower DMI during hot weather reduces nutrients available for absorption, and absorbed nutrients are used less efficiently. An excess of degradable dietary protein is undesirable because of energy costs to metabolize and excrete excess N as urea. Optimizing ruminally undegraded protein improves milk yield in hot climates. Mineral losses via sweating (primarily K) and changes in blood acid-base chemistry resulting from hyperventilation reduce blood bicarbonate and blood buffering capacity and increase urinary excretion of electrolytes. Theoretical heat production favors feed ingredients with a lower heat increment, such as concentrates and fats, whereas forages have a greater heat increment. Improved dietary energy density and the lower heat increment associated with the inclusion of dietary fat must be coupled with limitations to fat feeding to avoid ruminal and metabolic disorders. Numerous nutritional modifications are used for hot weather feeding; however, many need further investigation to achieve specific recommendations. 相似文献
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应用灰色关联度分析法评价放牧绵羊增重和羊毛生长的营养限制因素 总被引：1，自引：0，他引：1
本文应用灰色系统理论中的灰色关联度分析法,对影响放牧绵羊生产性能的主要营养限制因素进行了研究。关联度分析结果表明,饲粮粗蛋白质水平是影响绵羊体重变化的主要营养因素,饲粮代谢能的影响次之;影响育成母羊羊毛生长速度的主要营养因素是其干物质采食量;而成年母羊羊毛生长的营养限制因素是饲粮粗蛋白质水平。影响绵羊采食量的主要营养因素是饲粮代谢能浓度,其次是牧草质量。影响牧草消化率的主要营养因素是绵羊瘤胃发酵水平,其次是牧草中的木质素含量。 相似文献
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Potential for manipulation of the rumen fermentation through the use of recombinant DNA techniques 总被引：19，自引：0，他引：19
Recombinant DNA techniques offer a new approach to the study and eventual genetic manipulation of rumen bacteria to modify the rate and extent of nutrient digestion within the rumen. The foreign genes cloned into a rumen bacterium undoubtedly will have to enhance its ability to compete; otherwise, the new trait will be lost from the highly competitive environment within the rumen. As a general rule, the types of metabolic activities amenable to gene cloning may be those that enhance substrate versatility or eliminate a dependence of a specific rumen bacteria on cross-feeding by other rumen microorganisms. Enhanced substrate diversity and bypassing cross-feeding probably will become more important as the use of highly refined feeds and waste materials from the food and other industries are used in greater quantities to meet the dietary needs of ruminants. 相似文献
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Dietary fiber (DF), divided into soluble dietary fiber (SDF) and insoluble dietary fiber (IDF), has attracted increasing attention in the field of pig nutrition. Although DF reduces nutrient digestibility and inhibits energy deposition in most cases, fiber-rich feeds have been widely used in pig diets. This is not only because of lower feed costs, but also from the continuous discovery about the nutritional value of DF, mainly including the improvement of piglet intestinal health and sow reproductive performance. The addition timing has also been further considered, which potentially enables the nutritional value of DF to be accurately used in applicable pig models. Furthermore, fiber degrading enzymes have been shown to alleviate the anti-nutritional effects of DF and have ensured the improvement effect of fiber on intestinal health in young piglet models. However, the regulatory effect of fiber on pork quality is still unclear, which requires consideration of the wide range of fiber sources and the complexity of the basic diet composition, as well as the impact of pig breeds. Taken together, future research needs to gain more insight into the combined effects of SDF and IDF, processing methods, and addition timing to improve the nutritional value of DF, and further explore the physiological functions and regulatory mechanisms of DF fermentation products short-chain fatty acids in pigs. 相似文献
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We assessed the effects of nutrient supply and dietary bulk, both increasing with hay intake, on O2 uptake and nutrient net fluxes across the portal-(PDV) and mesenteric- (MDV) drained viscera, and the rumen in adult ewes. Four ewes, fitted with a ruminal cannula, with catheters in the mesenteric artery, the portal, mesenteric and right ruminal veins, and with a blood flow probe around the right ruminal artery, were used in a 4 x 4 Latin square design. Treatments consisted of 500 g DM/d hay (LL, low bulk and low nutrient supply), 500 g DM/d hay + infused nutrients (LH, low bulk and high nutrient supply), 750 g DM/d hay + infused nutrients (MH, medium bulk and high nutrient supply), and 1,000 g DM/d hay (HH, high bulk and high nutrient supply). Infused nutrients consisted of volatile fatty acids (VFA) and casein dissolved in salts and infused continuously in the rumen to provide the same amount of metabolizable energy (7.6 MJ/d) and digestible protein (63 g/d) for LH, MH, and HH. Both increases in bulk and nutrient supply increased O2 uptake in the MDV and PDV. Dietary bulk stimulated mainly blood flow, whereas nutrient supply stimulated mainly O2 extraction rate. The O2 uptake by the rumen was not significantly affected by hay intake, although blood flow increased due to nutrient supply. Increase in hay intake had no effects on portal net release of lactate and net uptake of glucose but increased VFA, 3-D-hydroxybutyrate, ammonia, and amino acids (AA) net release and urea net uptake across PDV. The increase in portal nutrient net fluxes with hay intake was entirely related to the increase of nutrient supply for VFA, 3-D-hydroxybutyrate, ammonia, and urea, irrespective of the amount of casein infused for AA. Dietary bulk had no effect on total energy net release in the portal vein. We conclude that despite the increase in portal O2 uptake, increasing dietary bulk had no significant impact on portal recovery of energy. In ruminal tissues, which were the main site of energy absorption, O2 uptake appeared low and was not sensitive to dietary manipulation. In contrast, in mesenteric tissues, which contribute poorly to energy absorption with forage diets, O2 uptake appeared high and very sensitive to dietary manipulation. 相似文献
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Urara Watanabe Koji Okamoto Akio Miyamoto Takeshige Otoi Osamu Yamato Chenga Tshering Mitsuhiro Takagi 《Animal Science Journal》2013,84(5):389-394
Ten reared cows of a Japanese Black cattle herd in Kagoshima prefecture, Japan, exhibited extremely low blood urea nitrogen (BUN) concentration (2.6 ± 0.6 mg/dL). Examination of dietary feed nutrition and relevant pastureland soil content suggested a correlation with crude protein (CP) deficiency or unbalanced nutritional dietary feeds. Thirteen months after the introduction of a dietary remedial measure (bean cake supplementation), BUN, total cholesterol and albumin concentration from five of the original 10 cows increased significantly compared with their values of before the dietary remedy. The postpartum day open period was significantly lower after the dietary remedial measure than that before it. The abnormally low BUN levels of the cattle herd may be due to inadequate dietary nutritional content, primarily from the imbalance of total digestible nutrient and CP of the feed and far lower han average CP value. In conclusion, routine examination of serum biochemical parameters in Japanese Black breeding cattle may be a useful strategy for determining subclinical metabolic failure of cattle herds, and consequently, its effect on reproductive performance of the herd. 相似文献
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本文对泾川县三元杂交肉牛的营养状况进行调查。发现日粮营水平不能满足肉牛生长发育的需要。建议提高肉牛日粮营养水平,并加强饲养管理,促进泾川县肉牛业的快速发展。 相似文献