代乳料-犊牛料不同哺育方案对0～2月龄断奶公犊生长发育的影响

试验旨在为中国荷斯坦犊牛的早期断奶人工培育提供参考。选择品种来源一致、体重(38.00±2.83)kg、平均出生时间1.83 d的健康中国荷斯坦奶公犊36头,采用L9(34)正交试验设计,研究代乳料中添加以甘露寡糖为主的非抗生素营养调控剂、补充以消化酶为主的外源复合酶制剂、以大豆浓缩蛋白为主的非乳源性蛋白不同替代比例以及代乳料-犊牛料不同哺育方案对早期断奶犊牛初生~2月龄生长发育的影响。结果显示,4因子对犊牛初生~2月龄平均日增重(ADG)调控效果的最佳优化组合为:非抗生素营养调控剂0.36%、非乳源性蛋白85%、复合酶制剂0.20%以及哺育方案代乳料7周+犊牛料1周过渡,对ADG的影响分别为802、779、754和770 g。初生~1月龄以非乳源性蛋白为主效因子,1~2月龄以非抗生素营养调控剂为主效因子。中国荷斯坦公犊初生~2月龄体尺与体重的回归公式为:体重(kg)=胸围(m2)×体斜长(m)×96.08-10.80。结果表明,在合理添加以甘露寡糖为主的非抗生素营养调控剂与补充外源复合酶制剂的条件下,代乳料中使用85%的非乳源性蛋白对初生~2月龄中国荷斯坦公犊可取得良好的增重效果。     

早期断奶不同哺育方案对2～6月龄犊牛生长发育与DMI的影响

为研究中国荷斯坦犊牛早期断奶不同哺育方案对断奶后2~6月龄生长发育与DMI的影响,选择品种来源一致、初生~2月龄(61日龄)阶段采用代乳料-犊牛料不同过渡时间哺育方案、实测平均体重(81.96±9.06)kg的健康中国荷斯坦公犊36头,按体重相近的原则随机分9组,以前期哺育方案、能量饲料构成,以及甘露寡糖、微生态制剂不同添加水平为试验因子,采用L9(34)正交试验设计,探索犊牛早期断奶代乳期代乳料-犊牛料不同过渡时间哺育方案对2~6月龄生长发育及DM采食能力的影响。结果显示,试验犊牛2~6月龄的生长强度依次为体重>胸围≈体斜长>管围>体高,以体重为最大,其次为胸围和体斜长;体重估测回归方程为:体重(kg)=胸围2(m)×体斜长(m)×84.06+13.48。对ADG的调控效果,2~4月龄以0.08%甘露寡糖最佳,"7+1"过渡与之相近,比设定水平可提高ADG 10.95%(P<0.05)以上;4~6月龄以"7+1"过渡为优,0.08%甘露寡糖与之相近,比设定水平可提高ADG 11.12%(P<0.05)以上。对DMI的调控效果,2~4、4~6月龄均以"7+1"过渡最优,比设定水平相对提高DMI 10.00%以上;0.08%甘露寡糖与之相似。以能量饲料构成的调控效果相对为小。结果表明,中国荷斯坦犊牛早期断奶代乳期采用7周代乳料+1周犊牛料过渡的前期哺育方案,断奶后犊牛料添加0.08%甘露寡糖、0.10%复合微生态制剂,犊牛料能量饲料构成采用普通玉米可显著提高ADG和增强青粗饲料采食能力。     

日粮蛋白能量比对中国荷斯坦犊牛生长性能及饲料利用率的影响

试验旨在研究粗蛋白质与消化能之比（CP∶DE）对3～5月龄中国荷斯坦犊牛生长性能及饲料效率的影响。选取30头70日龄断奶后正常过渡的中国荷斯坦犊牛,分为A、B、C 3组,每组10头,饲喂CP∶DE(g/Mcal) 分别为50.0∶1、 52.0∶1、54.9∶1的日粮,试验期90 d。A、B、C 3组间平均日增重（ADG）依次为0.83、0.80和0.81 kg/d,组间无显著差异。A、B、C 3组间饲料效率分别为4.29、4.24、3.96 kg/d,组间差异不显著,但有随着蛋白能量比升高而升高的趋势。3组间粗蛋白质和干物质的表观消化率随着日粮蛋白能量比增加而增加;干物质和有机物的表观消化率随着日龄的增加而降低;磷的表观消化率在3月龄后趋于稳定。血清尿素氮含量随着日粮蛋白能量比的升高而升高。综合平均日增重、饲料利用率、营养物质表观消化率等各方面的因素,在本试验条件下,蛋白能量比为50.0∶1的日粮就能满足3～5月龄平均日增重为0.8 kg/d的中国荷斯坦犊牛的生长需要。     

不同能量水平日粮中添加复合酶制剂对荷斯坦公牛生长发育及血液生化指标的影响

试验旨在研究不同能量水平日粮中添加复合酶制剂对荷斯坦公牛生长发育及血液生化指标的影响。选择20头6月龄健康的荷斯坦奶公牛,随机分组为5组,分别为高能量日粮加酶组、高能量日粮组、低能量日粮加酶组、低能量日粮组和对照组,每组4头,日粮综合净能摄入量分别为35.26、35.26、30.63、30.63、32.83 MJ,各组日粮粗蛋白质含量基本相同。试验结果表明,①在高能量水平条件下,添加复合酶制剂的试验组组间日增重差异不显著,而在低能量水平条件下,添加复合酶制剂的试验组组间日增重相差达0.14 kg,差异显著(P<0.05);②能量水平相同的条件下,添加复合酶制剂的试验组在胴体重、肌肉重、净肉率及屠宰率等指标上均高于未添加复合酶制剂的试验组;③本试验5种日粮对荷斯坦奶公牛血液生化指标产生了一定影响,能量水平及复合酶制剂均有提高血液中碱性磷酸酶、乳酸脱氢酶和总胆固醇的趋势。因此,复合酶制剂在低能量水平下饲喂效果较为明显,通过血液生化指标与屠宰指标的相关性分析得出,碱性磷酸酶和乳酸脱氢酶可能是反映并监控荷斯坦奶公牛生长发育和消化代谢的重要指标。     

不同来源的玉米干酒糟饲料对泌乳期奶牛的影响

试验证明,将代乳料中的粗蛋白(CP)含量从16%提高到26%,以每日进食率为体重的1.5%(干物质基础)饲喂奶牛公犊,可提高犊牛ADG、G/F和瘦肉组织沉积率。然而,日粮CP对上述指标的影响可能在不同程度上依赖于代谢能的摄入。因此,美国伊利诺伊大学的Bartlett等利用1周龄内的荷斯坦奶牛公犊进行试验,测定不同进食率和能量相同但CP含量不同的乳清蛋白代乳料对其生长性能和机体组分的影响。     

膨化豌豆对3月龄奶公犊增重效果的影响

试验旨在研究膨化豌豆粉替代日粮中玉米和豆粕对3月龄奶公犊日增重、饲料报酬的影响。选择85日龄左右的断奶荷斯坦奶公犊30头,根据日龄、体重随机分为对照组、试验组,每组15头,对照组组饲喂不含豌豆的全价日粮,试验组饲喂含有12.70%膨化豌豆粉的全价日粮。预试期15 d,试验期31 d。结果表明：试验组日粮中添加12.70%膨化豌豆粉替代对照组中的玉米和豆粕,试验结束时两组牛体重差异不显著,平均日增重差异显著,对照组较试验组平均日增重高0.21 kg;添加膨化豌豆粉的试验组饲料报酬高于对照组,每千克增重降低饲料消耗量0.1 kg,降低饲料成本0.42元。     

膨化豌豆对3月龄奶公犊增重效果的影响

试验旨在研究膨化豌豆粉替代日粮中玉米和豆粕对3月龄奶公犊日增重、饲料报酬的影响。选择85日龄左右的断奶荷斯坦奶公犊30头,根据日龄、体重随机分为对照组、试验组,每组15头,对照组组饲喂不含豌豆的全价日粮,试验组饲喂含有12.70%膨化豌豆粉的全价日粮。预试期15 d,试验期31 d。结果表明:试验组日粮中添加12.70%膨化豌豆粉替代对照组中的玉米和豆粕,试验结束时两组牛体重差异不显著,平均日增重差异显著,对照组较试验组平均日增重高0.21 kg;添加膨化豌豆粉的试验组饲料报酬高于对照组,每千克增重降低饲料消耗量0.1 kg,降低饲料成本0.42元。     

日粮蛋白能量比对3-5月龄后备奶牛乳腺发育及相关激素的影响

试验旨在研究粗蛋白与消化能之比(CP∶DE)对3～5月龄中国荷斯坦犊牛乳腺发育及相关激素的影响。选取30头70日龄断奶后正常过渡的中国荷斯坦犊牛,分为A、B、C3组,每组10头。饲喂CP∶DE(g/MJ)分别为13.5∶1、13.7∶1、14.6∶1的日粮,试验期90d。结果表明:A、B、C3组间平均日增重依次为0.83、0.80、0.81kg/d(P>0.05),试验牛乳头长度变化都随日龄的增加而增加(P>0.05),孕激素随着后备牛日龄的增加而增加,蛋白能量比为14.6∶1处理组后备牛的催乳素和生长激素的浓度显著高于蛋白能量比为13.5∶1和13.7∶1处理组(P<0.05)。3-5月龄后备奶牛生长速度及乳腺发育在日粮蛋白能量比为13.5∶1-14.6∶1范围内没有显著差异。     

甘露寡糖对荷斯坦奶牛产奶量及乳常规的影响

近年来,大量试验结果表明,甘露寡糖(mannan oligosaccharide,MOS)可明显降低肠道疾病发病率,降低饲料霉菌的毒副作用,提高奶牛免疫力.试验旨在研究甘露寡糖对荷斯坦奶牛奶常规的影响.选用80头2胎或超过2胎,体质量及产奶量相似,均处于泌乳后期的健康中国荷斯坦奶牛,随机分为试验组与对照组,平均胎次为3胎.对照组饲喂基础日粮,试验组在基础日粮中添加甘露寡糖(20 g/(d·头)),饲喂90 d.试验前和试验中进行奶样采集,并记录和测定产奶量及各个乳常规指标.结果表明,试验组奶牛的产奶量、乳脂率和体细胞数产生显著差异,而牛奶中蛋白含量差异不显著.试验结果显示,在日粮中添加一定量的甘露寡糖对荷斯坦奶牛产奶量及乳常规有有益的影响.     

玉米不同加工方法对初生犊牛生长特点、瘤胃发育及瘤胃参数的影响

用初生的荷斯坦犊牛作为试验动物,在开食料中分别添加33%整粒玉米( WC)、干滚玉米( DRC)、湿滚压玉米( RC)或蒸汽压片玉米( SDC) ,研究玉米不同加工方法对初生犊牛采食量、生长发育、瘤胃及血液代谢产物和瘤胃发育的影响。试验一,选用92头2±1日龄的荷斯坦犊牛(公犊5 2 ,母犊4 0 )开始饲喂开食料,试验期4 2 d。每天测定开食料干物质( DM)采食量和排粪量,每周测定犊牛生长情况及血液指标。4周龄时,采用安乐死的方法屠宰12头小公牛( 3头/组) ,取瘤胃组织,测定上皮发育情况。试验二,选用7日龄(±1d)荷斯坦小公牛做瘤胃瘘管,2～6周中连续取血样和瘤胃液样品进行测定。在试验一,犊牛在断奶前及整个试验期,DRC组干物质采食量显著高于RC组和SFC组,而WC组显著高于SFC组。DRC组犊牛断奶乳后平均日增重显著高于SFC组。SFC组犊牛血液中挥发性脂肪酸的浓度显著高于其它各且。SFC组与DRC组或WC组相比,4周龄犊牛瘤胃粘膜乳头长度及瘤胃壁厚度均有明显增加。在试验二,WC组与其它各组相比,有效提高了瘤胃PH,降低了挥发性脂肪酸的浓度;SFC组显提高了瘤胃中丙酸的产量;而RC组瘤胃丁酸的产量明显提高,表明玉米不同加工方法影响采食量、生长速度和瘤胃参数。RC组犊牛体重、饲喂效率和瘤胃发育的情况与其他组无差异,但促进了     

关于能量营养及能量饲料的几个问题

2003年9月份,普渡大学的Dr.Harmon教授第十一次来到中国,在6省(市)举办为期将近一个月的养猪生产培训班,向中国的养猪同仁传授技术,交流信息。虽然谈论的仍是老话题和最基本的营养素,但每次的重新讨论和结合我国养猪生产的思考,都会让参会的每一位有新的认识和收获,现把部分观点总结如下:能量是“生命之火”,是生命的源动力,是研究领域永恒的话题,也是大家既熟悉却又模糊的营养素。我们可以去描述和感受到能量,却在生产应用中难以去准确测量的一个第一重要的指标。因此,在我们的实际生产应用中,有关能量的偏差之处还有多处。学过《饲养学》…     

Metabolisable energy studies with Turkeys: Metabolisable energy of dietary ingredients

Experiments have been performed to determine the metabolisable energy, content (ME) of a range of dietary ingredients for the young turkey. Determinations were carried out by a total collection procedure and test ingredients were substituted into a basal diet composed of commercially obtainable ingredients. Test ingredient ME values were obtained by regression analysis and extrapolation based on two levels of inclusion. For cereals and where possible for protein concentrates, inclusion levels of 20 and 40% were used.

The ME values found with the turkey were generally similar to those found with the chick; however, values obtained with the turkey for more fibrous materials appeared to be substantially greater than have been found with the chick. A simultaneous comparison of the ME values obtained for samples of oats and maize with turkeys and chicks showed that the ME value to be assigned to oats was approximately 8% greater when determined with the turkey than when determined with the chick. Similar values for maize were obtained with the two species.     

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。     

Investigations of energy metabolism in weanling barrows: the interaction of dietary energy concentration and daily feed (energy) intake

Much of our understanding of energy metabolism in the pig has been derived from studies in which the energy supply was controlled through regulated feed intake. In commercial situations, where ad libitum feeding is practiced, dietary energy concentration, but not daily feed intake, is under producer control. This study evaluated the interactive effects of dietary energy concentration and feeding level (FL) on growth, body composition, and nutrient deposition rates. Individually penned PIC barrows, with an initial BW of 9.5 +/- 1.0 kg, were allotted to 1 of 9 treatments in a 3 x 3 factorial arrangement plus an initial slaughter group (n = 6) that was slaughtered at the beginning of the trial. Three NE concentrations (low, 2.15; medium, 2.26; and high, 2.37 Mcal of NE/kg) and 3 feeding levels (FL: 100, 80, or 70% of ad libitum access to feed) were investigated. Daily feed allowance for the restricted-fed pigs was adjusted twice per week on a BW basis until completion of the experiment at 25 +/- 1 kg of BW. Average daily gain, ADFI, and G:F were unaffected by NE (mean = 572 g, 781 g, and 0.732 g/g, respectively). Average daily gain and ADFI, but not G:F, increased (P < 0.05) with FL. Empty body lipid concentration increased with dietary NE concentration and with FL; a significant (P < 0.01) interaction revealed that empty body lipid concentration increased most rapidly as ADFI increased on the highest energy diet. Empty body lipid concentration was greatest in pigs with ad libitum access to the high-NE diet. Empty body protein concentration decreased with increasing NE (P < 0.05) but was not affected by FL. Empty body protein deposition (PD) increased with increasing FL (P < 0.001), but not with NE. Empty body lipid deposition (LD) and the LD:PD ratio increased (P < 0.01) in pigs with ad libitum access to the high-NE diet. In conclusion, NE did not interact with FL on growth, body protein concentration, or PD, suggesting that the conclusions regarding energy utilization obtained from experiments using restricted feed intake may not easily be applied to pigs fed under ad libitum conditions. The interactive effects of NE and FL on body lipid concentration, LD, and the LD:PD ratio indicate that changes in dietary energy concentration alter the composition of gain without necessarily changing overall BW gain. Consequently, the composition of gain is an important outcome in studies on energy utilization.     

Impact of energy and protein restriction on energy expenditure of gestation in twin-bearing ewes

This study aimed to investigate the impact of energy and protein restriction on energy expenditure of gestation (EE_gest) in twin‐bearing ewes. Multiparous twin‐bearing ewes were fed either adequate (A: n = 10) or restricted to 60% of energy and protein requirements (R: n = 10) during the last 6 weeks of gestation. Whole‐body energy expenditure (EE) and retained energy (RE) were calculated from respiratory gaseous exchange combined with nitrogen balance at 7, 5 and 2 weeks prepartum. Twin lamb birth weight was lower in the R group compared to those in the A group (7.9 ± 0.31 vs 9.3 ± 0.19 kg, P < 0.01). The EE_gest was lower in the R group than the A group (4.6 vs 5.9 MJ/day, SE = 0.30, P < 0.01). Between 5 and 2 weeks prepartum, EE_gest contribution to the whole‐body EE significantly (P < 0.01) increased from 39% to 45% and from 34% to 40% in the A and R groups, respectively. Based on kg conceptus weight, both EE_homeorhetic (from 292 to 270 kJ/kg/day, SE = 6.2, P < 0.001) and EE_conceptus (from 259 to 177 kJ/kg/day, SE = 23.8, P = 0.02) decreased between weeks 5 and 2 prepartum. The EE_conceptus tended to be lower (P = 0.06) in the R group than the A group both at 5 weeks (219 vs 298 kJ/kg/day, SE = 32.8) and 2 weeks (from 138 to 217 kJ/kg/day, SE = 30.1) prepartum. In conclusion, energy and protein restriction reduced energy expenditure of gestation calculated per kg conceptus weight. The decrease may be associated with energy expenditure of conceptus growth and maintenance.     

Prediction of digestible energy and gross energy digestibility of feeds and diets in ostriches

1. The aim of this study was to assess regression equations able to predict the digestible energy (DE) and gross energy digestibility (GEd) of feed ingredients and diets for ostriches.

2. Results of chemical-nutritional characteristics from 17 ingredients (two varieties of maize, two barleys, oat, triticale, wheat bran, soybean meal, sunflower meal, beet pulp, maize silage, alfalfa hay, 4 alfalfa meals and lupin) and 12 experimental diets were used in a stepwise procedure.

3. Acid detergent lignin (ADL) was the first independent variable included in the model to predict the DE of all the samples (R² = 0.65 and Residual Standard Deviation (RSD) 1.02). When the concentration of ash, acid detergent fibre (ADF) and crude fibre were included in the model, the R² value of the regression equation increased (from 0.65 to 0.85) and RSD decreased (from 1.02 to 0.48).

4. The ADL concentration was also the first independent variable chosen by the stepwise regression analysis for the estimation of GEd from chemical-nutritional characteristics of feeds, explaining 57% of the total GEd variation. The concentrations of crude protein and ADF included at the second and third steps in the model increased the R² (up to 0.70 and 0.73, respectively) and decreased the RSD values (from 0.29 to 0.21 and 0.20, respectively). When other variables as crude fibre, ash and gross energy were included in the model, the coefficient of determination and the RSD strongly improved (0.85 and 0.12, respectively).     

Net energy,energy utilization,and nitrogen and energy balance affected by dietary pea supplementation in broilers

Pea starch consists predominantly of C-type of amylopectin chain which is more resistant to digestive enzymes than A-type of starch thus slowly digested in poultry. It was hypothesized that the presence of slowly digested pea starch in broiler diets will increase net energy and the efficiency of energy utilization in broilers. Two experiments were performed to investigate starch digestibility of pea at different incubation times (in vitro study) and the effect of dietary pea on heat increment and net energy in broilers using an open-circuit respiratory calorimetry system (in vivo study). One-day-old Ross 308 male broilers were fed a common starter crumble from d 1 to 10 and standard grower diets thereafter. At d 21, birds were transferred to the chambers each housing 2 birds. Each treatment was replicated 6 times with 2 identical runs of 3 replicates per treatment. A wheat-soybean meal-based diet was used as a control and the treatment diet contained 500 g of pea/kg pea. In vitro study showed that pellet processing increased (P < 0.001) starch digestibility, particularly at shorter times for wheat and a much larger response for pea. Birds offered the pea-based diet had lower (P = 0.002) feed intake, lower (P = 0.020) body weight gain, but a similar (P > 0.05) FCR compared to those offered the wheat-based diet. Net energy (NE) and apparent metabolizable energy (AME) values were higher in the pea-based diet than in the wheat-based diet (P = 0.037 for NE and P = 0.018 for AME). Heat production, respiratory quotient, heat increment of feed, efficiency of utilization of gross energy for AME, and efficiency of utilization of AME for NE did not differ (P > 0.05) between the 2 treatments. There was no effect (P > 0.05) of pea on the total tract digestibilities of dry matter, crude protein and ash, but the total tract digestibility of starch was higher (P = 0.022) in the pea-based diet compared to the wheat-based diet. This study provides insight into the energy metabolism of broilers offered a pea-based diet and indicates that dietary pea supplementation increases dietary AME and NE but has no effect on heat increment of feed and the efficiency of energy utilization in broilers.