饲喂代乳粉对早期断奶犊牦牛生长性能的影响及经济效益分析

为研究饲喂代乳粉对早期断奶犊牦牛生长性能的影响以及产生的经济效益,试验选用30日龄,体重(26±2.6)kg犊牛30头,随机分成3组,每组10头犊牛,每组公母各半,Ⅰ、Ⅱ组分别饲喂高蛋白含量代乳粉、高脂肪代乳粉,对照组按传统方法进行母乳喂养。结果表明:饲喂代乳粉能显著提高早期断奶犊牦牛的体增重和日增重(P0.05);饲喂代乳粉对早期断奶犊牦牛的体高、体斜长和胸围没有显著影响(P0.05);犊牦牛早期断奶能显著提高母牦牛的发情率、受胎率(P0.05),缩短牦牛生产周期,显著提升代乳粉饲喂阶段的经济效益(P0.05)。综合分析,饲喂代乳粉对早期断奶犊牦牛无论在犊牛生产性能方面还是经济效益方面都有显著效果,应在生产中推广应用。     

饲喂不同营养水平代乳粉对犊牛生长性能的影响

选择体重和出生日期相近、健康状况良好的荷斯坦公犊牛30头,随机分为3组（试验I组、Ⅱ组和Ⅲ组）,每组10头,研究了饲喂不同脂肪和蛋白质水平代乳粉对犊牛生长性能的影响。不同处理代乳粉的营养水平分别为：试验I组,EE13％、CP22％;Ⅱ组,EE16％、CP24％;Ⅲ组,EE19％、CP26％。研究结果表明．犊牛的日增重随着代乳粉营养水平的升高逐渐提高,试验Ⅱ组和Ⅲ组的日增重分别比试验I组提高了35．45％和37．63％（P〈（1．05）．试验Ⅱ组和Ⅲ组的平均日增重差异不显著;饲喂高营养水平代乳粉具有降低犊牛腹泻的趋势;不同试验处理对犊牛开食料采食量无显著差异。综合分析饲喂不同营养水平代乳粉对犊牛生长和经济效益的影响,代乳粉的适宜营养水平为EE16％、CP24％。     

应用代乳粉培育放牧犊牦牛的生长效果和经济效益分析

通过研究不同营养水平的代乳粉对48头犊牦牛生长发育的影响及对其生产经济效益的分析,发现在本试验条件下:饲喂27%、29%蛋白质水平的代乳粉对犊牦牛的增重效果优于自然放牧牦牛;饲喂29%蛋白质水平代乳品的犊牛生长性能优于饲喂25%和27%蛋白质水平代乳粉的犊牛;对犊牦牛饲喂代乳粉的经济效益大幅优于天然放牧的犊牦牛,27%蛋白质水平代乳粉的投入回报率最高。     

饲喂站中代乳粉饲喂量对犊牛生长性能的影响

随着奶牛场规模化的发展,犊牛小群饲养模式被广泛应用,为了探索犊牛小群自动化饲喂站的使用方法及应用效果,试验通过引进荷兰犊牛饲喂站,选择出生日期和体重相近的母犊牛20头,随机分为对照组和试验组,每组10头,试验组哺乳期(4~70日龄)饲喂553 L液体代乳粉,对照组饲喂471 L液体代乳粉,定期监测犊牛生长指标。结果表明:试验组在30,45,60,75,90日龄的体重和不同阶段的日增重均高于对照组,但差异不显著(P0.05)。说明利用犊牛饲喂站同时增加代乳粉的饲喂量对犊牛的生长指标有增加的趋势。     

犊牛饮水的重要性与管理要点

犊牛阶段的生长发育状况对成年后生产性能的发挥具有极为重要的影响,所以犊牛的饲养管理非常关键。水是犊牛维持基础营养代谢和健康生长的重要营养元素,但是与代乳粉和开食料等日粮相比,容易被牧场忽视。本文分析了犊牛饮水的重要性及需水量与采食量的关系,讨论了犊牛饮水管理中的关键点,为加强犊牛饮水管理,提高犊牛阶段的培育管理水平提供指导。     

微生态代乳粉对犊牛生长性能影响

以膨化玉米和大豆为主要能量和蛋白原料,添加酵母粉、超强双歧因子等微生态制剂,配合形成微生态代乳粉,以鲜牛乳饲喂犊牛为对照,研究微生态代乳粉对犊牛生长性能与腹泻率的影响.试验结果表明,微生态代乳粉可完全满足犊牛生长需要,在生产性能方面等同或优于鲜牛乳饲喂效果,同时可降低犊牛腹泻率.     

代乳粉对犊牛生长性能及消化器官发育影响的研究

通过饲养试验、屠宰试验和组织切片观察,研究代乳粉对犊牛生长性能与消化器官发育的影响,共分3个试验.试验选取体况相近的新生犊牛20头,按照出生日期和体重相近的原则,随机分为2组,分别为试验组10头、对照组10头.试验组犊牛自出生第6天起开始训练采食代乳粉,6～20d为过渡期,自21日龄起全部饲喂代乳粉;对照组全部饲喂鲜牛乳,试验期共60 d.结果显示,犊牛采食代乳粉后,自出生到60d断奶,每头犊牛可节约鲜奶315 kg;体增重、日增重均优于对照组,但组间差异不显著(P＞0.05);自试验第40天开始,体高、体斜长、胸围均显著高于(P＜0.05)或有显著高于对照组的趋势(P＜0.10):腹泻发病率较对照组降低13.16%;犊牛采食代乳粉可促进小肠、食管及各胃室增重和发育.     

代乳粉对早期断奶犊牛生长的影响

旨在评价饲喂代乳粉对早期断奶犊牛生长及培育成本的影响。选取体重相近的新生犊牛45头,随机分为试验1组、试验2组和对照组;试验1组饲喂A品牌代乳粉,试验2组饲喂B品牌代乳粉,对照组饲喂牛场产鲜牛奶;测定各组实验犊牛的出生体重、1月龄体重和50日龄断奶体重;计算并比较各组犊牛培育成本。结果表明,各组犊牛的出生体重和1日龄体重差异不显著（P〉0.05）;试验1组和试验2组犊牛的50日龄断奶体重分别比对照组增加5.12、2.86 kg,且试验1组与对照组相比差异显著（P〈0.05）;试验1组和试验2组犊牛的平均日增重分别比对照组增加0.14、0.07 kg,且试验1组和对照组相比差异显著（P〈0.05）;试验1组与试验2组平均每头犊牛分别比对照组节约饲养成本198.8、222.0元。综上提示,使用代乳粉能够促进犊牛生长,降低犊牛的培育成本,提高养殖场的经济效益。     

不同代乳粉对早期断奶乳公犊生产性能的影响

为了研究不同代乳粉对早期断奶乳公犊生产性能的影响,试验选择日龄和体重相近、健康状况良好的荷斯坦公犊18头,采用完全随机设计分为3组,每组6头,对照组饲喂牛奶,试验1组饲喂国产代乳粉,试验2组饲喂进口代乳粉。结果表明:试验2组犊牛体重极显著高于对照组和国产代乳粉组(P0.01),且进口代乳粉组的利润最高,试验1组次之,对照组最低,但3组犊牛体尺指标和血液生化指标差异不显著(P0.05)。说明进口代乳粉无论在犊牛生产性能方面还是经济效益方面都优于国产代乳粉和牛奶。     

用代乳粉替代全乳饲喂牦牛犊的试验研究

为了探讨代乳粉替代全乳饲喂对牦牛犊生长发育的影响,选择日龄相近且健康的牦牛犊,按照抓阄的方法确定试验组(代乳粉)和对照组(全哺乳),每组30头。研究结果表明,海北高原牦牛犊可以提前到30日龄断奶,断奶后用代乳粉替代自然哺乳是可行的。代乳粉能够充分满足犊牛生长发育的营养需要,提高犊牛日增重,加快犊牛生长发育,缩短母牛的繁殖间隔。     

液体饲料饲喂量对哺乳期犊牛生长性能、消化代谢的影响

研究液态饲料的饲喂量对犊牛生长发育、营养物质消化吸收的影响。选取16头犊牛,分为2个处理组,按照体重的9.5%和11.0%分别饲喂代乳粉乳液,试验全期为8周,测定犊牛的体重、测量体尺,进行消化代谢试验。两组犊牛在增重、体长指数、体躯指数上没有显著性差异(P0.05);在营养物质的消化代谢上,11.0%组在3～4周时干物质吸收量、粗蛋白吸收量及代谢能均优于9.5%组(P0.05),而在5～6周时无显著差异(P0.05)。在本试验中,液体饲料的饲喂量为犊牛体重11.0%时对犊牛的生长性能具有较好的促进作用,并且对犊牛消化吸收营养物质有积极的影响。     

代乳粉用于早期断奶犊牛的效果研究

犊牛使用代乳品可以节省鲜奶，降低饲养成本，控制疾病的发生，促进消化系统的发育。试验用24头犊牛做试验，60日龄断奶。结果表明，代乳品组犊牛增重47．55千克；对照组增重41．72千克；吃代乳品的犊牛在30-60日龄的日增重达到1026克，高于对照组103克。吃代乳品的犊牛每增重1千克的直接饲料成本为15．13元，比鲜奶组犊牛低2．14元／千克。     

Economic analysis of feeding pasteurized nonsaleable milk versus conventional milk replacer to dairy calves

OBJECTIVE: To determine growth, morbidity, and mortality rates in dairy calves fed pasteurized nonsaleable milk versus commercial milk replacer and compare economics of feeding pasteurized nonsaleable milk versus commercial milk replacer in dairy calves. DESIGN: Clinical trial. ANIMALS: 438 dairy calves. PROCEDURE: Calves were assigned at 1 to 2 days of age to be fed pasteurized nonsaleable milk or a commercial milk replacer until weaned. Body weight was measured at the time of study enrollment and at the time of weaning, and any medical treatments administered and deaths that occurred prior to weaning were recorded. A partial budget model was developed to examine the economics of feeding pasteurized nonsaleable milk versus commercial milk replacer. RESULTS: Calves fed conventional milk replacer had significantly lower rates of gain (-0.12 kg/d [-0.26 lb/d]), lower weaning weights (-5.6 kg [-12.3 lb]), higher risk for treatment during the summer and winter months (odds ratio [OR], 3.99), and higher risk of death during the winter months (OR, 29.81) than did calves fed pasteurized nonsaleable milk. The estimated savings of feeding pasteurized nonsaleable milk, compared with milk replacer, was dollars 0.69/calf per day. The estimated number of calves needed to economically justify the nonsaleable milk pasteurization system was 23 calves/d. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dairy calves fed pasteurized nonsaleable milk have a higher growth rate and lower morbidity and mortality rates than do calves fed conventional milk replacer. Feeding pasteurized nonsaleable milk could be an economically viable strategy for dairy calf producers.     

The effect of unrestricted milk feeding on the growth and health of Jersey calves

This study was conducted to determine the effect of feeding high milk volumes on the growth rate, health and cross-sucking behaviour in group-fed Jersey calves. Three-day-old heifers (n = 120) in a seasonal calving dairy herd were randomly assigned to one of 6 treatment groups. Three groups received high milk volumes (HMV), consisting of ad libitum milk or milk replacer feeding twice a day, while 3 groups received restricted milk volumes (RMV), consisting of 2 l twice daily, during the pre-weaning period. After a pre-weaning period during which feeding was reduced to once daily, all calves were weaned at 42 days and monitored until 60 days of age. Adjusting for birth mass, birth date, dam parity and sire, average daily mass gain (ADG), both pre-weaning (days 0-42) and overall (days 0-60), was higher in HMV than in RMV calves (P < 0.001). After weaning, growth rates showed no differences and at 60 days of age the HMV calves maintained a 6.74 kg advantage in mean body mass (P < 0.001). The mean intake of dry starter feed was higher in RMV than in HMV calves. Overall feed conversion rate of HMV calves was 9.6 % better than RMV calves. However, the variable cost per kg mass gain was 12 % higher for HMV calves. In the RMV groups 75 % of calves showed cross-sucking behaviour pre-weaning and 18 % post-weaning, whereas in HMV calves the proportions were 2 % and 7 %, respectively. There was no significant effect of milk volume on the incidence of diarrhoea. We conclude that the feeding of high volumes of milk to Jersey calves has a positive effect on growth rate, without compromising health or reducing solid feed intake after weaning. However, the higher cost of such a feeding system may limit its implementation.     

Effects of the provision of large amounts of solid feeds to veal calves on growth and slaughter performance and intravitam and postmortem welfare indicators

Polish Friesian male calves (n = 78) were used to investigate the effects of innovative feeding plans based on the provision of large amounts of solid feeds on growth performance, welfare, and carcass characteristics of veal calves. Groups of calves (initial BW 71.5 ± 3.7 kg) were fed 1 of 3 treatments (26 calves/treatment): 1) milk replacer plus corn grain (CG), 2) milk replacer plus an 80:20 mixture (as-fed basis) of corn grain and wheat straw (CGS), or 3) milk replacer plus a 72:20:8 mixture (as-fed basis) of corn grain, wheat straw, and extruded soybean, respectively (CGSES). All the treatments provided at least 170 kg DM/calf from solid feed throughout the 206 d of fattening. Type and concentration of milk replacer were the same for all calves throughout fattening. Calves fed CGSES received 96% of the daily amount of milk replacer delivered to CG and CGS to balance the dietary CP content. No differences (P ≥ 0.063) among treatments were observed for growth performance and DMI. Health status of CG calves was less than CGSES calves, as indicated by the greatest (P < 0.001) proportion of milk replacer refusal events and the greatest (P < 0.001) incidence of treatments for respiratory disorders. Inclusion of straw and soybean in the solid feeds increased (P < 0.001) the daily intake of iron in CGS and CGSES as compared with CG; however, blood hemoglobin concentrations measured at d 5 and 31 were greater (P < 0.05) than when measured on d 80, 122, and 206 of fattening. Feeding treatment did not (P ≥ 0.107) affect HCW, dressing percentage, or carcass color. Calves fed CG had heavier (P < 0.001) reticulorumens and more (P < 0.001) developed rumens than CGS and CGSES calves, but 84% and 68% of CG rumens (P < 0.001) showed overt signs of hyperkeratinization and plaques, respectively. These alterations of rumen mucosa were not detected in CGSES calves, and only 8% of CGS calves had rumen plaques. Regardless of feeding treatment, postmortem inspection recorded a prevalence of more than 84% abomasal lesions. When feeding veal calves with large amounts of solids, it is advisable to avoid the provision of corn grain alone and replace part of the cereal with a roughage source to improve calf health and prevent rumen mucosa alterations.     

Growth of rearing calves in relation to lysine contents of milk replacer and calf starter and feeding frequency of milk replacer

In two factorial feeding experiments with 90 and 102 rearing calves the effect of addition of extra lysine to the milk replacer in combination with a low and high lysine content of the calf starter on dry matter intake and weight gain was studied. Once or twice daily milk feeding was also compared. The calves received milk replacer up to the age of 8 weeks and calf starter and hay ad libitum from the 3rd week on. The experiments lasted to the age of 12 respectively 10 weeks. In the first experiment increasing the lysine content of the milk replacer from 14.5 g/kg to 18.5 g/kg had no effect on dry matter intake and weight gain. In the second experiment increasing the content of lysine to 17 g/kg resulted in higher intake of dry matter and higher weight gain, but only in combination with a calf starter with a low lysine content (6 g/kg). In the first experiment twice daily milk feeding resulted in higher intake of concentrate and higher weight gain as compared to once daily. In the second experiment this was only so if the starter had the lower lysine content. Increasing the lysine content of calf starter from 7 to 8.5 g/kg had no effect on dry matter intake and weight gain in the preweaning period in the first experiment. In the second experiment increasing the lysine content from 6 to 8.5 g/kg led to higher intake of concentrate and higher weight gain. This effect was only seen if the milk replacer had no extra lysine added. In the postweaning period there was no effect of increasing the lysine content from 7 to 8.5 g/kg (Exp. I). Increasing the lysine content from 6 to 8.5 g/kg led to higher dry matter intake and higher weight gain (Exp. II). These results are discussed in the light of the partial degradability of the concentrate protein in the rumen and the effect of duodenally available lysine on feed intake and weight gain.     

Effects of feeding level of milk replacer on body growth,plasma metabolite and insulin concentrations,and visceral organ growth of suckling calves

The objective was to evaluate effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and allometric growth of visceral organs in suckling calves. Holstein bull calves (n = 8; 3–4 days of age) were fed either a low amount (average 0.63 kgDM/day, LM) or high amount (average 1.15 kgDM/day, HM) of high protein milk replacer until they were slaughtered at 6 weeks of age. Body weight (BW) at 4, 5, and 6 weeks of age, feed intake, average daily gain, and feed efficiency were higher in the HM than LM calves. The HM group had higher plasma glucose at 3 and 4 weeks of age and insulin levels after the age of 4 weeks compared with LM calves whereas no effect was detected on plasma nonesterified fatty acid or urea nitrogen concentrations. The HM calves had greater empty body weight (EBW), viscera‐free BW and most of the organs dissected than LM calves. Relative weights (% of EBW) of liver, spleen, kidneys, and internal fat were higher, whereas head and large intestine was lower in HM than LM calves. The results suggest that increased milk feeding levels would accelerate the growth of the body and specific organs.     

代乳粉在犊牛早期断奶技术中应用的试验研究

22头体重相近的荷斯坦犊牛随机分为2组,试验组饲喂代乳料,对照组饲喂新鲜牛奶。经60d的饲喂试验发现,试验组增重比对照组多5.3kg/头,且差异极显著(P<0.01),日增重比对照组提高了88.3g/d,差异极显著(P<0.01)。     

液态饲料饲喂量对0～2月龄犊牛生长性能的影响

本试验旨在研究液态饲料的饲喂量对犊牛生长性能及健康情况的影响。选取24头新生荷斯坦犊牛,随机分为3个处理,每个处理8个重复,每个重复1头牛,分别按照体重的9.5%、11.0%、12.5%饲喂代乳品乳液。试验全期为8周。测定犊牛的体尺、体重、采食量和记录粪便评分。结果显示:3组犊牛的采食量差异显著(P<0.05)。在日增重上,9.5%组的犊牛比11.0%组和12.5%组的犊牛低(P>0.05),且在3~4周龄时,表现出显著性差异(P<0.05)。在饲料转化率上,3组犊牛在0~6周龄内均不断改善,其中3~4周龄时11.0%组优于9.5%组和12.5%组(P<0.05)。3组犊牛的粪便指数均较低,但在添加开食料和羊草时,有所波动。在单笼饲养条件下,液态饲料中干物质占12.5%时,按犊牛体重的11.0%饲喂液态饲料可获得最佳生长性能。