鹅对几种原料代谢能值的测定

本试验以24只175日龄扬州鹅公鹅为试验对象,用真代谢能(TME)测定法,测定了鹅对玉米、豆粕、小麦麸、稻谷、棉籽粕、苜蓿粉6种原料的代谢能值。试验结果表明:1)鹅对玉米、稻谷、小麦麸、豆粕、棉籽粕、苜蓿粉的表观代谢能(AME)值分别为12.23、10.93、8.03、8.99、6.67、4.25MJ/kg;真代谢能值分别为12.89、11.59、8.93、9.85、7.60、5.19MJ/kg。2)测得6种原料的TME值高于AME值,且TME∶AME为1.05～1.25;TME值的变异系数(CV)小于AME值,表明TME值的稳定性优于AME值。     

影响家禽饲料代谢能的因素

家禽饲料代谢能受许多因素的影响。概括起来可分为3个方面:测定方法、试验动物和饲料本身。所有影响饲料消化吸收的因素均间接影响代谢能值。本文对这些因素进行分析讨论,并提出了各种解决办法。1测定方法从各种代谢能的定义上看,真代谢能(TME)>氮校正真代谢能(TMEn)>表观代谢能(AME)>氮校正表观代谢能(AMEn)(Wolynetz和Sibbald,1984)。目前普遍采用的测定方法是排空强饲法(Sibbald,1975)。由于试禽采食量较小,试验过程中每个操作的微小误差均会影响最终测定值。AME随采食量增加而升高。用内源排泄能(EEL)对AME进行校正(TME)可减…     

Comparative study of apparent metabolizable energy and net energy values of dephenolized cottonseed proteins for laying hens

Optimizing the energy utilization of nutrients and ensuring maximum benefits are continuous goals for livestock producers.The net energy (NE) value of feed reflects its nutritional value in the precision feeding system.An experiment was conducted to determine the apparent metabolizable energy (AME)and NE values of 3 types of dephenolized cottonseed protein (DCP) for Hy Line Brown hens aged 42 to 45 weeks using the reference diet substitution method.A reference diet based on corn soybean meal was...     

家禽饲料有效能值的测定及影响因素

<正>客观准确地评定饲料原料和饲料的有效能值是开发利用饲料资源及优化饲料配方的主要决策依据。实践中,为了经济地配制家禽日粮,就要准确地测定各种饲料原料中(尤其是能量饲料)的有效能值,低估了能值,就会在最低成本日粮中拒用一种成分,但     

A dynamic model of metabolizable energy utilization in growing and mature cattle. II. Metabolizable energy utilization for gain

Component models were developed to predict the net efficiency of ME utilization for gain in cattle and to predict daily gain using recovered energy as the input. These models were integrated into a single model to predict daily gain from ME available for gain. One component model predicts the net efficiency of ME utilization for gain using constant partial net efficiencies of 0.2 and 0.75 for ME retention as protein and fat, respectively. This model predicts net efficiency of ME utilization for gain as a function of the ratio of the energy recovered in protein to the total energy recovered. The other component model predicts daily gain as a function of recovered energy and is represented by a system of ordinary differential equations that are numerically integrated on a daily basis. This model was developed by reformulating the equations in a published body composition model that uses daily gain to predict composition of gain since recovered energy is a function of gain and composition of gain. The equations in the two component models interact in that net efficiency is used to predict recovered energy from ME for gain, and in turn, recovered energy is used to predict gain in empty BW, which determines net efficiency through composition of gain. The numeric integration procedure provides an iterative solution for net efficiency. Simulated response of net efficiency for Hereford x Angus steers at 400 kg of empty BW decreased from 0.57 to 0.52 on diets with ME densities of 3.1 and 2.6 Mcal/kg of DM, and restricting the lower-quality diet to 75% of ad libitum intake resulted in a simulated net efficiency of 0.47. These responses in net efficiency were shown to be a result of composition of gain, with leaner gains resulting in lower net efficiencies.     

Digestibility and metabolizable energy values of processed cassava chips for growing and finishing pigs

Determinations of digestibility of dry matter (DM), digestible energy (DE), and metabolizable energy (ME) in cassava chips with different levels of crude fiber (CF) were measured in growing pigs (20 kg) and finishing pigs (60 kg). The treatments were (1) cassava starch (0% CF), (2) peeled cassava chips (2.5% CF), (3) non-peeled washed cassava chips (3.9% CF), and (4) non-peeled and non-washed cassava chips (5.2% CF). In the growing pigs, peeled cassava chips, non-peeled washed cassava chips, and non-peeled and non-washed cassava chips had DM digestibility of 87.51%, 78.63%, and 73.89%, respectively. Their DE was 3.69, 3.49, and 3.32 Mcal/kg DM, respectively (DE of cassava starch is 3.90 Mcal/kg DM). ME was 3.54, 3.35, and 3.19 Mcal/kg DM, respectively (ME of cassava starch is 3.74 Mcal/kg DM). On the other hand, in the finishing pigs, the digestibility of DM was 89.13%, 80.63%, and 76.13%, respectively. Their DE was 3.72, 3.53, and 3.43 Mcal/kg DM, respectively (DE of cassava starch is 3.91 Mcal/kg DM). ME was 3.57, 3.38, and 3.29 Mcal/kg DM, respectively (ME of cassava starch is 3.75 Mcal/kg DM). These values increased with decreasing CF content, and the peeled cassava chips had the highest values (P < 0.01). These suggest that the digestibility values of DM, DE, and ME of cassava chips is inversely related to the CF content in cassava chips. It is recommended that cassava chips be peeled for better nutrition for growing and finishing pigs.     

添加木聚糖酶的小麦型日粮对肉仔鸡表观代谢能的影响

试验旨在比较研究不同木聚糖酶产品对小麦代谢能的影响。624只AA肉仔鸡随机分为13组,每组8个重复,每个重复6只鸡。其中1组为基础日粮对照组,另外12个处理组组成一个3×4二因素(小麦和木聚糖酶)完全随机试验。其中小麦设4个水平(样本),木聚糖酶设3个水平(不加酶、加酶A 400 mg/kg、加酶B 257.56 mg/kg),两种酶的添加活性均为1 500 U/kg饲料。采用外源指示剂法评定添加木聚糖酶制剂前后小麦代谢能的变化。结果表明,不同小麦样品的AME和AMEn有极显著差异(P0.01),其中以小麦1和小麦4能值最高。日粮中添加两种木聚糖酶均极显著提高了小麦的AME和AMEn(P0.01),其中以酶B的效果最为明显,极显著高于酶A(P0.01)。添加酶A平均提高小麦AME和AMEn 420 kJ/kg和300 kJ/kg,添加酶B平均提高小麦AME和AMEn 790 kJ/kg和710 kJ/kg。     

A dynamic model of metabolizable energy utilization in growing and mature cattle. I. Metabolizable energy utilization for maintenance and support metabolism

Models to predict heat production attributable to maintenance and support metabolism in growing and mature cattle were developed on the basis of three concepts. The first concept is that animals fed fixed amounts of the same diet achieve weight equilibrium over an extended feeding period, and that the ME consumed at weight equilibrium is the maintenance requirement. The second concept is that a part of the heat production resulting from ME consumed above the maintenance requirement is associated with an elevation of vital functions (support metabolism), and this heat production can be modeled as a function of the level of feeding. The third concept is that previous levels of nutrition affect current estimates of heat production, and that this impact can be modeled as a delayed response in heat production associated with support metabolism. Experimental data on feed consumption showed that maintenance requirements varied in simple proportion to BW, not only for different breeds of mature cattle at BW equilibrium, but also for calves and growing steers held at BW stasis. Experimental data in which different breeds of cattle achieved weight equilibrium when fed fixed amounts of a specific diet were used to estimate breed parameters associated with maintenance for 21 breeds of cattle and 15 biological types of crossbred cattle. Level of feeding was estimated as a multiple of the maintenance intake and used to model heat production associated with support metabolism. Other experimental data on growing cattle were used to estimate breed parameters for predicting heat production associated with support metabolism for 21 breeds of cattle and 15 biological types of crossbred cattle. A distributed lag function was used to model the delayed response in heat production associated with support metabolism with changes in plane of nutrition. The models were tested by simulating experimental data for three breeds of weaned steers finished on high-energy diets. Results for the total heat production associated with maintenance and support metabolism expressed on a unit BW basis showed a similar response with stage of maturity when compared with other experimental data.     

True metabolisable energy, heat increment and net energy values of two high fibre foodstuffs in cockerels

1. The yields of true metabolisable energy (TME) and net energy (NE) from chaya leaf meal and wheatfeed were mcasured in tube-fed cockerels. 2. TME, 5.76 MJ/kg, from chava leaf meal was lower than from wheatfeed, 8.39 MJ/kg. The total heat increment attributable to the feeding of chaya leaf meal was 1-7 times greater than that of wheatfeed. 3. The net efficiency of utilisation of ME (k) from chaya leaf meal was 0.64, while that from wheatfeed was 0.86. The role of different chemical composition, especially the high fibre content of the materials, is discussed. 4. The metabolisable energy and net energy values derived from chava leaf meal represented 0.34 and 0.23 respectively of its gross energy content. The combination of lower TME and lower net efficiency of utilisation led to chaya having a NE value, 3.86 MJ/kg, which was only 0.53 that of wheatfeed.     

木聚糖酶与肉仔鸡小麦日粮代谢能之间当量关系的研究

小麦中的阿拉伯木聚糖(NSP)造成肉鸡肠道食糜黏度,降低营养物质的消化吸收率(明根·朝格图,1996)。木聚糖酶通过水解小麦中的木聚糖,消除其抗营养作用,从而提高蛋白质、脂肪、淀粉等营养物质的消化率,同时伴随着饲料代谢能的提高(卢铮,张日俊,1997)。     

Growth, body composition, and visceral organ mass and metabolism in lambs during and after metabolizable protein or net energy restrictions

Three trials were conducted to assess effects of metabolizable protein and NE deficiencies on changes in body composition, organ mass and metabolism, and animal growth performance during restriction and realimentation. Growth of lambs was restricted to achieve no change in BW for periods of 5 to 6 wk by limiting intake of metabolizable protein or NE. In Trial 1, changes in body composition and visceral organ mass and metabolism during restriction were compared to unrestricted controls using 36 lambs. Trial 2 was designed to investigate changes in growth, body composition, and visceral organs during restriction and realimentation periods using 44 lambs. Trial 3 was limited to evaluation of differences in performance and carcass characteristics of previously restricted and unrestricted ram lambs (15 total). Results of Trial 1 indicated that liver weights were decreased with nutrient restrictions. Body protein mass was conserved in energy-restricted (ER) lambs and lost in protein-restricted (PR) lambs. Fat was mobilized at similar rates for PR and ER lambs. In Trial 2, liver and intestinal weights, as well as in vitro oxygen consumption by liver slices, were decreased with nutrient restrictions. The reductions persisted after 2 wk of realimentation, yet no compensatory growth was observed. Feed intakes were increased gradually during the first 2 wk of realimentation. Composition of gain during the realimentation period was similar to that of unrestricted lambs. In Trial 3, neither gain nor feed efficiency during realimentation was enhanced as a result of previous nutrient deficiencies. Absence of compensatory growth in Trial 3 is possibly attributable to differences in gastrointestinal fill. Lambs subjected to short-term PR and ER seem to have similar recuperative capacity.     

日粮不同能量水平对育成鸡营养物质代谢及肌肉品质的影响

本试验从日粮不同能量水平对育成期塞北乌骨鸡营养物质代谢及肌肉品质进行了研究。结果表明,母鸡在代谢能(ME)为11.51MJ/kg时氮表观代谢率最大为56.08%,公鸡在ME为12.34MJ/kg时氮表观代谢率最大为49.31%,从氮平衡来看,均为正平衡。公鸡和母鸡在ME为12.96 MJ/kg时摄入能量最高,代谢能也最高。能量水平的提高可适当提高塞北乌骨鸡公鸡和母鸡的胸肌率及公鸡的腿肌率,对母鸡的腿肌率的影响不明显。     

Comparison of energy deposition and utilization of feedstuffs and rations between growing and adult pigs.

The effect of energy deposition and the utilization of feedstuffs and rations were compared between growing and adult pigs. The good agreement in the data leads to the conclusion, that the energy deposition effect of feedstuffs and rations in growing pigs can be estimated with an equation based on measurements in adult pigs. Exceptions are feedstuffs which are digested bacterially to a relatively high part in the large intestine, as e.g. sugar beet pulp, raw potatoes or similar feed.     

A dynamic model of metabolizable energy utilization in growing and mature cattle. III. Model evaluation

Component models of heat production identified in a proposed system of partitioning ME intake and a dynamic systems model that predicts gain in empty BW in cattle resulting from a known intake of ME were evaluated. Evaluations were done in four main areas: 1) net efficiency of ME utilization for gain, 2) relationship between recovered energy and ME intake, 3) predicting gain in empty BW from recovered energy, and 4) predicting gain in empty BW from ME intake. An analysis of published data showed that the net partial efficiencies of ME utilization for protein and fat gain were approximately 0.2 and 0.75, respectively, and that the net efficiency of ME utilization for gain could be estimated using these net partial efficiencies and the fraction of recovered energy that is contained in protein. Analyses of published sheep and cattle experimental data showed a significant linear relationship between recovered energy and ME intake, with no evidence for a nonlinear relationship. Growth and body composition of Hereford x Angus steers simulated from weaning to slaughter showed that over the finishing period, 20.8% of ME intake was recovered in gain. These results were similar to observed data and comparable to feedlot data of 26.5% for a shorter finishing period with a higher-quality diet. The component model to predict gain in empty BW from recovered energy was evaluated with growth and body composition data of five steer genotypes on two levels of nutrition. Linear regression of observed on predicted values for empty BW resulted in an intercept and slope that were not different (P < 0.05) from 0 and 1, respectively. Evaluations of the dynamic systems model to predict gain in empty BW using ME intake as the input showed close agreement between predicted and observed final empty BW for steers that were finished on high-energy diets, and the model accurately predicted growth patterns for Angus, Charolais, and Simmental reproducing females from 10 mo to 7 yr of age.     

水产饲料原料生物利用率

一、简述 饲料原料的营养价值不仅取决于其化学成分,而且取决于鱼类对这些养分或能量的吸收和利用率。建立完善的生物利用率数据库是科学设计配方的基础,而水产动物上。虽已进行了大量的工作,然而系统性、准确性尚有较大的差距。针对我国的主要养殖品种,本文将已有研究作一小结。以期为深入研究和为水产饲料配制提供参考。     

饲粮代谢能水平对22～42日龄黄羽肉鸡生长性能、胴体品质以及部分血液生化指标影响的研究

试验以岭南黄鸡为代表,研究饲粮代谢能水平对22～42日龄黄羽肉鸡生长性能、胴体品质以及部分血液生化指标的影响。试验结果表明:①随饲粮代谢能升高,试鸡平均日增重有增加趋势,平均日采食量有降低趋势,而饲料转化率得到极显著改善(P<0.01);②饲粮代谢能水平对试鸡胴体品质有显著(0.010.05)。     

Effects of diet type and metabolizable energy intake on tympanic temperature of steers fed during summer and winter seasons

A summer study and a winter study were conducted using an incomplete factorial structure in a complete randomized design. Within season, the factors studied were 1) type of diet, which included 2 levels of ME, classified as either concentrate (3.04 Mcal of ME/kg) or roughage (2.63 Mcal of ME/kg) diets, and 2) daily ME intakes (MEI) of 11, 18, and 25 Mcal of ME/d for the roughage diets and 18, 25, and 32 Mcal of ME/d for the concentrate diets. In Exp. 1 (summer study), 30 steers (5 steers/treatment combination) were used to collect tympanic temperatures (TT). In Exp. 2 (winter study), 24 steers (4 steers/treatment combination) were used to collect TT. Mean TT was 0.3°C greater for summer than winter (38.9 vs. 38.6°C, respectively; P < 0.05). Steers fed diets based on concentrate tended to display greater TT than steers fed diets based on roughage. Season × diet × hour interactions were found for TT (P = 0.01). In the winter, greater TT (P < 0.05) were found from 0900 to 1400 h when an equal amount of MEI was derived from a concentrate-based vs. roughage-based diet. In cattle fed roughage-based diets during the summer, TT = 38.63 + 0.0114?MEI, whereas for cattle fed concentrate-based diets, TT = 38.69 + 0.0114?MEI. During the winter, for cattle fed a roughage-based diet, TT = 37.65 + 0.0856?MEI - 0.0018?MEI(2), whereas for cattle fed a concentrate-based diet, TT = 35.37 + 0.2635?MEI - 0.0051?MEI(2). In summary, results demonstrate that increases in the energy of the diet resulted in increases in TT. However, the response was dependent on season of the year, with a linear response in TT for summer and a quadratic response during winter.     

Effects of diet forage:concentrate ratio and metabolizable energy intake on isolated rumen epithelial cell metabolism in vitro

Crossbred wether lambs were used to assess the effect of altered forage:concentrate ratio and metabolizable energy intake on metabolism of substrates by ruminal epithelium using an isolated cell system. Lambs (n = 28; 20.1 +/- 3 kg BW) were assigned randomly to a factorial arrangement of dietary treatments consisting of either 75% forage or 75% concentrate fed once daily at either .099 or .181 Mcal ME x(kg BW(.75))(-1) x d(-1) for 52 d. After a 52-d feeding period, isolated rumen epithelial cells (IREC) were incubated in the presence of an oxidizable substrate with a single 14C label (acetate, propionate, butyrate, glucose, glutamate, and glutamine) at concentrations ranging from .1 to 50 mM, and substrate oxidation to 14CO2 or metabolism to beta-hydroxybutyrate (beta-HBA), acetoacetate, pyruvate, and lactate was determined. For all substrates, oxidation to CO2 was concentration-dependent and saturable within the physiological range. Differences in substrate oxidation to CO2 by IREC at specific substrate concentrations did not affect Vmax (maximal rate of substrate oxidation, nmol oxidized to CO2 x 1 x 10(6) cells(-1) x 90 min(-1)) and K(ox) (concentration of substrate at which half Vmax oxidation rate is achieved, mmoles/L) estimates for the dietary treatments. Production of beta-HBA from butyrate by IREC from the lambs fed 75% forage was not affected by ME intake; however, production was elevated by high ME intake of the 75% concentrate diet (diet x intake interaction; P < .02). Acetoacetate production from butyrate by IREC from lambs fed at high ME intake was greater (P = .001) than from those fed at low ME intake. Lactate and pyruvate production from glucose, glutamate, and propionate were generally unaffected by dietary treatment; however, rate of glutamine metabolism to lactate and pyruvate by IREC was increased with increased ME intake. The observed changes in metabolite production rates across groups did not affect the predicted Vmax and K(ox) parameter estimates. The estimated K(ox) values corroborate that VFA are the primary oxidizable fuels used by ruminal epithelial cells while illustrating that other substrates such as glucose, glutamate, and glutamine would not be expected to be oxidized extensively in vivo due to the high K(ox) relative to substrate concentrations in vivo. In conclusion, the capacity of isolated ruminal epithelial cells to oxidize substrates was largely unaffected by ME intake or dietary forage:concentrate ratio of the diet.