牛能量需要量测定方法研究进展

能量是牛日粮的第一限制性养分,确定牛能量需要量是合理配制牛饲料、提高饲料利用效率的重要前提.牛能量需要量的测定方法主要有饲养试验、消化代谢试验、呼吸测热法及比较屠宰法等,论文对上述方法进行了简要综述,为合理进行牛能量需要量评定提供参考.     

优质肉鸡的能量需要量研究进展

能量是家禽日粮的第一限制性养分,确定优质肉鸡能量需要量是合理配制优质肉鸡饲料、提高饲料利用效率的重要前提。优质肉鸡在我国家禽产业体系中占有重要的地位,研究其能量需要量对提高优质肉鸡的生产性能具有重要意义。文章主要就优质肉鸡能量需要量方面的研究进展进行了综述,对能量需要量的研究方法和影响因素进行分析,对研究优质肉鸡能量需要量的相关原始文献中的数据、观点和结论进行整理和归纳,为优质肉鸡精细化饲养和日粮的精准配制提供参考。     

高产奶牛的饲养

奶牛业成功的关键是合理的饲养产奶牛群,因为饲料的成本占牛奶生产总成本的一半以上.为了使奶牛企业获得利润,奶牛必需具有高产的遗传潜力,并以最低成本的饲料获得最高产奶量.奶牛需要的营养物质包括:水、能量、蛋白质、矿物质和维生素.干奶牛的饲养产奶牛的合理饲养应从干奶期开始.干奶牛应与牛群的其它牛分开管理,因其营养需要量与泌乳牛完全不同,混在一起不可能达到理想的饲养效果.为获得最高     

不同营养水平对黄颡鱼春片鱼种生长的影响

采用正交设计法L9(34)配制9种试验饲料,以6g左右黄颡鱼900尾为试验动物随机分为9组进行68d饲养试验,对黄颡鱼配合饲料中蛋白质、脂肪、总能、无机盐需要量及最适能量蛋白比进行了研究。结果表明:H—9号饲料能量16.0083MJ/kg。蛋白质44.35%水平适宜于黄颡鱼的营养需要,黄颡鱼饲料的最适能量蛋白比(E/P=MJ/kg)为35.4～36.5。     

不同水平的代谢能和以可消化氢基酸和总氢基酸需要量为基础的日粮配方对雄性肉仔鸡生产性能的影响

为了评估日粮中不同水平的能量和日粮氨基酸需要量为基础的配方法的影响，本试验选择294只雄性肉仔鸡，采用7因子完全区组设计。试验因子包括不同的能量水平（7个能量水平）和日粮氨基酸需要量（总氨基酸和可消化氨基酸）为基础的配方法。以氨基酸需要量为基础的配方法对肉仔鸡累计饲料采食量没有显著影响。     

育肥牛能量需要量的研究进展

能量是动物营养需要重要组成部分，是动物维持生命活动和生产的基础。研究育肥牛能量需要量是合理利用饲料资源、提高生产性能、高效科学养殖肉牛的关键因素。本文对目前国内外有关育肥肉牛能量需要量及其代谢的研究进展进行了归纳总结，以期为生产中更加科学配制育肥肉牛日粮及健康养殖提供参考依据。     

泌乳牛日粮能量,蛋白质平衡的研究

本研究以美国NRC（1998）奶牛营养需要中的能量和吸收蛋白需要量的计算公式以及瘤胃微生物蛋白产量的估测方程为基础，探讨了泌乳牛不同日粮能量浓度下的干物质需要量，自由采食所能达到的最大泌乳量时的蛋白质需要量，以及在不同蛋白质降解率时的日粮粗蛋白水平等。由于泌乳牛处于较高的代谢水平，所以饲料转化效率与对各种营养物质的需求都较高。特别是对能量和蛋白质的需要，往往由于供给不足而影响产奶量的提高。粗饲料质量较差时，能量和蛋白质供给不足的问题变得更为严重。1计算公式及方法1．1泌乳牛能量需要泌乳的代谢能（ME）转化…     

猪饲料的配比原则

饲料标准是对动物实行科学饲养的重要依据。经济合理的饲料配方必须根据饲养标准所规定的营养物质需要量指标进行设计。在选用的饲养基础标准的基础上,可根据饲养实践中动物的生长或生产性能等情况作适当的调整。1多样性猪的饲料应尽量满足配料的多样性,保证营养的全面。一般由能量饲料、蛋白质饲料、矿物质饲料、维生素饲料4类组成,配合时以达到饲料易消化、适口性好为目的。合理搭配多种饲料,以发挥各     

黄颡鱼营养学研究系列:鱼苗对不同营养水平饲料利用效果的比较

以蛋白质、能量和预混料为试验因素,按照L9(34)正交设计表,设计3因素3水平试验,对平均体重为0.40g的9000尾黄颡鱼鱼苗进行30天的饲养试验。结果表明,饲料蛋白水平对鱼苗生长起主要作用,其次为预混料,能量最小,饲料蛋白水平对增重率和饲料转化率有显著影响(p<0.05)。本次试验得出,黄颡鱼鱼苗最适蛋白质需要量为45%,最适能量需要量为14MJ/kg。     

大尾寒羊能量和蛋白质需要量及析因模型研究

选用100只大尾寒羊作为试验动物,采用饲养对比试验、消化代谢试验、比较屠宰试验、低氮日粮平衡试验、气体能量代谢试验和绝食代谢试验,系统研究了大尾寒羊不同生理阶段的蛋白质、能量代谢规律及需要量.在分别研究蛋白质、能量维持和生产需要量的基础上,采用析因法,获得大尾寒羊不同生理状态下的能量需要量析因模型14个,蛋白质需要量析因模型13个,制定出了不同生产水平条件下的能量和蛋白质需要量标准.     

Feeding phosphorus (P) to cattle: A new basis for Nordic recommendations

Phosphorus (P) is an essential nutrient and significant safety margins have until now been included in both feeding recommendations for cattle and allocation of P in practice. However, there is a need to optimize the utilization of P in cattle and thereby minimize its allocation and excretion. This demands well-defined requirements and availabilities of P in feeds as well as fairly precise use of this knowledge in practice. The purpose of this paper is to review the current knowledge and to give proposals for feeding phosphorus to cattle in relation to physiological requirement, availability of phosphorus in feeds, and minimal excretion of P. There is scientific and practical basis for a reduction of recommendations and allocation of P to cattle in the Nordic countries. No evidence or indication is found that surplus P relative to physiological requirement is beneficial. Future P feeding recommendations should continuously be based on the factorial method. The quantitatively most important improvement will be the increase and differentiation of the TAC value (true availability coefficient), which can be raised from 0.55 to 0.65 and 0.70 for the most common feeds. However, there is still no basis for a specific TAC for an individual feedstuff. When applying the recommended P allocation, it will be possible to increase the utilization of P in, e.g. high producing dairy cows, to 35–40%.     

杂交优质肉牛屠宰测定

选择10－25月龄的二元和三元杂交肉牛共10头进行分阶段育肥，共135d。第一阶段补予能量饲料，第二阶段除补给能量饲料外，添加矿质元素和蛋白质饲料，其它按传统方法饲养，现场测定，屠宰率为55.43%，净肉率为44.77%，肉骨比为4.2:1。大理石花纹评定，特级占20％，优一级占60％，优二级占20％，均达到优质牛肉标准，3头牛的样品实验室分析，嫩度即剪切力值均低于美国规定的3.62kg，达到了优质牛肉的标准，臀肉、背最长肌分析，富含多种氨基酸。     

Recycled poultry bedding as cattle feed.

Since the 1950s, recycled poultry bedding has been used as an economical feedstuff for beef cattle. It has been extensively studied at several experiment stations around the world with regard to its safety and nutritional aspects. It will continue to be closely scrutinized as the public increases its awareness of agricultural issues. As this study was being prepared, the news media was "spotlighting" bovine spongiform encephalopathy. Currently, in the United States there is a ban on incorporation of mammalian-derived protein feeds into ruminant diets. This has led to a requirement of beef cattle producers signing affidavits indicating that they had met this obligation. Some poultry companies use ruminant meat and bone meal in broiler diets when least-cost formulation indicates that it is economically desirable. This then poses the question of whether feeding RPB to beef cattle should be permitted if the birds had been fed ruminant meat and bone meal. It also raises the question of whether cattle grazing pastures fertilized with RPB are exposed to ruminant meat and bone meal. Because of the importance of pasture fertilization as a waste disposal solution for the poultry industry, it seems that the issue will be quickly resolved by omitting the ruminant meat and bone meal from poultry diets should concerns increase. Use of RPB, like many byproduct feeds, requires a higher level of management expertise than traditional feeds. Despite the potential problems discussed in this study, an informed beef cattle producer can gain a financially competitive edge by using RPB. A simple processing method, deep-stacking under polyethylene sheeting, can produce a safe product that will provide a complete diet when blended with an energy source and supplemented with some long-stem fiber. The diets can be used for both brood cows and stocker calves for extended periods of time, and the practice of feeding RPB is safe for both cattle and consumers [45]. Economic parameters will influence the future use of RPB; however, the general public's perception and acceptance will ultimately determine its long-term use.     

生长期秦川牛能量代谢规律与需要量研究

本试验旨在研究生长期秦川牛能量代谢规律与需要量。选择30头体况良好、体重[(336.33±18.28)kg]相近的生长期秦川牛公牛,随机分为5组,每组6头牛,分别饲喂按我国《肉牛饲养标准》(NY/T 815—2004)提供的预期平均日增重900 g/d所需净能的85.0%(Ⅰ组)、92.5%(Ⅱ组)、100.0%(Ⅲ组)、107.5%(Ⅳ组)、115.0%(Ⅴ组)配制的5种试验饲粮。采用饲养试验和消化代谢试验测定秦川牛生长性能及能量代谢指标,并建立消化能和代谢能需要量预测模型。预试期10 d,正试期42 d。结果表明,Ⅲ组秦川牛平均日增重为880.15 g/d,较预期的结果略低;Ⅳ组平均日增重达到最大值(1 160.10 g/d),能量利用效率最高;总能消化率、总能代谢率和消化能代谢率平均值分别为(76.44±3.23)%、(66.75±3.16)%、(87.31±0.54)%;秦川牛的消化能和代谢能需要量的回归方程分别为:DER=0.778W0.75+37.05ADG;MER=0.668W0.75+33.49ADG[DER为消化能需要量(M J/d),MER为代谢能需要量(M J/d),W0.75为单位代谢体重(kg),ADG为平均日增重(kg/d)]。综合得出,生长期秦川牛的维持消化能和代谢能需要量分别为0.778、0.668 MJ/(kg W0.75·d),每千克增重的消化能和代谢能需要量分别为37.05、33.49 M J。     

The energy requirement of young female cattle. 2. Substance and energy metabolism

The second installment of information on studies over several years of the energy requirement of young female cattle comprises data of the feed intake, the digestibility and metabolizability of the rations used as well as the nitrogen and energy balances of the test animals in six experiments with varying rearing intensities, in which the N, C and energy balances as well as rumen physiologic values were measured monthly using the respiration test technique. Of four experiments, measured values are available over the whole rearing period from calf to calving. The results received from 680 interpretable test periods are-separated for the six experiments--arranged in aggregate form according to live weight range in order to characterize the development of nutrient and energy metabolization processes at various rearing intensities. The results form an essential basis for the derivation of the energy requirement of young female cattle according to factorial criteria.     

Effect of compensatory growth on regulation of growth and lactation: response of dairy heifers to a stair-step growth pattern

The primary objective of this study was to improve the productive efficiency of growth via optimal use of both high fiber-low quality and high energy-high protein feeds in diets for growing dairy cattle. Twenty Holstein heifers were randomly assigned to either a control or treatment group. The control diet met the National Research Council (NRC) requirement for .45 kg/d gain, with heifers calving at 24 to 26 mo of age. The test groups were fed according to a 5-2-5-2 mo schedule in which the nutrient density was alternately 15% below or 40% above the NRC requirement. Results showed that the heifers on the test dietary regimen (compensatory growth) gained more and consumed less, resulting in significantly improved efficiency of growth (body gain/dry matter intake X 100), energy (body gain X 1,000/metabolizable energy (ME) intake) and protein utilization (body gain/protein intake X 100) in comparison to control animals (13.0 vs 7.3%; 57.9 vs 32.6 g/Mcal ME; 96.5 vs 54.2%, respectively). Marked changes in average concentration of urea-N, glucose, triglycerides, cholesterol and lecithin cholesterol acyltransferase activity in blood were seen for test heifers during the stair-step growth phase (i.e., alternating maintenance and compensatory). Evidence from this experiment suggests that the phased growth (stair-step) system offers a simple, practical and cost-effective method for raising dairy heifers.     

2019年肉牛饲料与营养评价的国外研究进展

文章旨在了解饲料与营养对肉牛生产性能、消化性能、瘤胃发酵以及甲烷(CH₄)排放的影响。文章综述了2019年国外的相关文献报道,主要从精饲料、粗饲料及饲养营养综合评价3个方面进行综述。精饲料集中于各种蛋白质饲料和能量饲料的研究。粗饲料研究侧重于粗饲料品种和加工方式对不同生理阶段肉牛生产性能、消化性能和CH₄产生的影响。饲料营养综合评价主要侧重于犊牛期研究,并对育肥期和放牧期肉牛的饲料营养进行评价,以根据肉牛的生理阶段特点,选择适宜的饲料原料,并合理搭配和调制日粮以改善瘤胃菌群结构,充分提高养分利用率。     

牛秸秆及牧草的补饲与替代率

秸秆及天然牧草是我国养牛的主要饲料，但喂秸秆及牧草营养不全，需要补饲，只要补饲得当就可增加干物质食入量。替代率是表示食入量的重要指标。本文综述了牧草补饲、秸秆的补饲及舍饲粗料的能量补饲与替代率，以便提高干物质食入量。促进牛的生产力。     

Energy requirements of young female cattle. 6. Energy requirements

Results taken from 6 experiments with young female cattle comprising 477 metabolism periods served the derivation of the animals energy requirement in the development range greater than 125 kg live weight according to the factorial method. The energy requirement per kg LW0.75 and day, calculated from metabolism data, was independent of the stage of development and the intensity of feeding. It averaged 455 +/- 66 kJ metabolizable energy/kg LW0.75.d and 250 +/- 37 kJ NEFcattle/kg LW0.75.d respectively. The partial energy requirement for live weight gain, expressed in net energy fat, was equivalent to the energy content of the live weight gain. Energy retention and thus energy requirement per kg live weight gain increased with the live weight and reached a maximum of 26 MJ. Energy retention per kg live weight gain largely depended on the intensity of feeding and the stage of gravidity. Restrictive energy supply and progressing gravidity decreased energy content in the weight gain. The influences mentioned were taken into consideration on the derivation of the partial requirement for live weight gain. Equations were developed for the estimation of the energy requirement of young female cattle, which can be applied to both gravid and non-gravid cattle.     

不同蛋白源饲料对秦川肉牛屠宰性能及牛肉品质的影响

[目的]试验旨在研究不同蛋白源饲料对秦川肉牛日增重、屠宰性能及肉品质的影响。[方法]选择20头体重相近、健康状况良好的12月龄左右的秦川肉牛(母牛)为试验动物,随机将试验牛分为5组,各组分别饲喂5种不同精饲料。试验结束后,对照组(31%豆粕组)、试验Ⅰ组(36%菜籽粕组)和试验Ⅳ组(42%紫苏饼组)各选3头参试牛进行屠宰。[结果]试验Ⅳ组的全期总增重、平均日增重和屠宰率均显著高于对照组(P<0.05);试验Ⅳ组背最长肌中干物质和粗蛋白含量均高于其他两组,但各组间均差异不显著(P>0.05);对照组和试验Ⅰ组大理石花纹均是3级,试验Ⅳ组大理石花纹是4级。[结论]本试验条件下,精饲料中添加42%的紫苏饼能够提高肉牛日增重和屠宰率,能够提高牛肉中氨基酸的含量和粗蛋白水平。