浅谈新生犊牛的饲养管理

<正>1饲喂培育哺乳犊牛应注意从单胃消化转为复胃消化,从奶的营养到饲草营养的过渡。1.1及时喂初乳母牛产后5~7d分泌的乳汁称为初乳。初乳中含有多种抵抗疾病的免疫物质和维生素。犊牛出生后1h内必须吃到初乳,没有吃到初乳的犊牛很难得到正常的生长发育。1.2哺喂常乳犊牛饲喂初乳5~7d后,即可开始哺喂常乳。因初乳、常乳、混合乳的营养成分差异很大,犊牛最好吃其母亲常乳10~15d后,再饲喂混合常乳,以免造     

初乳饲喂优化方案对犊牛健康状况和生长性能的改善作用

本试验选取体重相近、健康状况良好的40头新生荷斯坦母犊牛,随机分为两组。对照组犊牛饲喂未经巴氏杀菌的初乳和常乳,试验组饲喂经过巴氏杀菌的初乳和常乳,观察期60d,旨在研究巴氏杀菌的初乳和常乳对犊牛健康状况和生长性能的改善作用。试验结果显示,巴氏杀菌的初乳和常乳能极显著减少乳中细菌总数和总大肠杆菌数,减少犊牛被动免疫失败率,改善犊牛腹泻状况,显著提升0~60日龄内的犊牛日增重,在一定程度上促进犊牛的均衡发育。     

犊牛饲养误区

<正>1)初乳饲喂不当。初乳尤其是产犊第1天的初乳对犊牛生长最为重要。有的养殖户在饲喂犊牛时缺乏合理的初乳饲喂计划,不重视对初乳的储存,大量初乳被废弃掉。2)常乳喂量不足。15日龄后正常犊牛体重达55 kg以上,犊牛将开始尝试咀嚼干草或青贮料和舔食精饲料,出现反刍行为。但此时犊牛前胃的发育还不完全,主要依靠皱胃进行消化。一些奶农只顾眼前利益,误认为犊牛也会吃草和饲料了,便减少奶的喂量或在     

饲养奶牛犊存在的问题及改进措施

初乳是指奶牛生产后7天内所分泌的乳汁，其成分和lO天以后母牛分泌的常乳存在着很大差别，尤其是产犊第一天的初乳最为重要，其中富含大量免疫球蛋白，它对初生牛犊的正常生长发育和从中获得抗体、增强抵抗力十分重要，是其他食物所无法代替的。初生犊牛食量小，而奶牛产后初乳丰富。农户在饲喂犊牛时缺乏合理的初乳饲喂计划．不重视对初乳的储存，大量初乳被废弃掉．或用于饲喂其他大犊牛，而所产犊牛只能得到7天的初乳，7天后母牛转为常奶生产期，小犊牛也只能用常奶饲喂了。有的奶农用初乳饲喂犊牛，喂量时多时少，奶温时高时低。易造成犊牛消化不良．引起腹泻．导致体况柔弱。     

基于蛋白质组学技术分析初乳和常乳摄入对初生犊牛肝脏蛋白表达的影响

【目的】试验旨在对犊牛肝脏蛋白进行蛋白质组学分析,筛选与初乳、常乳摄入相关的蛋白。【方法】以经产荷斯坦母牛分娩的9头公犊牛为研究对象,随机分为初乳组(CI)、常乳组(M)和对照组(CT),每组3头。初乳组和常乳组犊牛分别饲喂初乳和常乳,于出生后24 h屠宰;对照组未饲喂初乳或常乳,于出生后2 h屠宰。采用Label-free蛋白组学技术对3组犊牛肝脏的蛋白表达谱进行分析,以Q<0.05为阈值筛选各组间的差异表达蛋白,并进行GO功能和KEGG通路富集分析。【结果】在犊牛肝脏中共鉴定到3 901个蛋白,其中在初乳组、常乳组和对照组中分别鉴定到3 521、3 646和3 548个蛋白,有3 202个蛋白在3组中共表达。对差异表达蛋白进行分析显示,初乳组和常乳组犊牛肝脏中共筛选出287个差异表达蛋白,主要参与细胞代谢、应激反应、生长发育和氧化还原等生物过程,显著富集通路为内吞作用、氨基酸代谢和氧化磷酸化;初乳组和对照组犊牛肝脏中共筛选出154个差异表达蛋白,主要参与细胞代谢、单组织过程和肌酸合成等生物过程,显著富集通路为氨基酸代谢、黏着斑和内吞作用等。【结论】饲喂初乳的犊牛肝脏中差异表达...     

不同液体日粮对断奶前犊牛生长发育影响的研究进展

现代化、规模化的奶牛养殖牧场中犊牛液体日粮主要包括初乳、常乳、异常乳和代乳粉等,尤其是异常乳使用较多;通常在液体日粮饲喂犊牛过程中会使用巴氏杀菌、酸化、发酵和添加营养增强剂等方式进行处理。目前关于如何使用液体日粮以达到较高安全性、利用价值和养殖效益一直争议不断,特别是对于异常乳的使用已成为研究热点。本文对不同液体日粮对犊牛采食、生长、胃肠道发育及其菌群变化的影响,以及对犊牛成年后产犊和泌乳量的影响进行阐述,为今后犊牛液体日粮的使用和研究方向提供理论参考。     

犊牛饲喂方法

犊牛初乳期结束到断奶称为常乳期。此阶段犊牛体尺、体重增长迅速,胃肠道结构功能变化大,此阶段的饲养是由真胃消化向复胃消化转化、由饲喂奶品向饲喂草料过渡的一个重要时期。该阶段的饲     

初乳的发酵试验

初乳是指母牛产犊后7天以內所分泌的乳。它具有很高的营养价值,对新生犊牛十分重要,是必需的食物。目前初乳除部分饲喂刚生下的犊牛外,大量剩下的初乳既不能供人饮用,又不能混入常奶中作乳制品。因此,每年有大量的初乳废弃或用来喂猪,未能充分利用,为了更合理地利用初乳,我们进行了发酵初乳的制作和饲喂试验。     

初乳与常乳混合自然发酵饲喂犊牛效果观察

为合理利用初奶,降低犊牛培养成本。我们在参照天津塘沽农场等兄弟单位,用发酵初乳饲养犊牛的经验的基础上,进行了初乳与常乳混合自然发酵饲喂犊牛试验,仅将试验情况报告如下:     

饲喂发酵初乳犊牛的胃肠道微生物区系

引言发酵初乳是一种受欢迎的犊牛饲料。已经证明饲喂发酵初乳犊牛的体重增加比词喂全乳的犊牛大或相似。在一些试验中,词喂发酵初乳犊牛的腹泻发生率比词喂全乳或代乳品的犊牛低,而在另外一些试验中,腹泻的发生率则相似。本报告的目的是研究饲喂发酵初乳和饲喂全乳对幼年犊牛肠道中不同种细菌数量的影响。     

Antioxidants in Bovine Colostrum

Quality, content and properties of colostrum are crucial for the neonate and its further development. Due to essential differences between intrauterine and extrauterine environment, the neonate is exposed to oxidative stress conditions. Colostrum apart from nutrient and immunological components should contain antioxidative systems necessary for the protection against reactive oxygen species. This review describes available data on enzymatic and non-enzymatic antioxidants in colostrum. Due to the fact that the literature concerning bovine colostrum is scanty, the information based on bovine mature milk determinations as well as other species is provided. Bovine colostrum is used not only by calves, but also for the production of hyperimmunized colostrum, medicines or feed supplements. Quality of colostrum influences quality of mature milk. This is another reason, except from health of neonate, why antioxidative properties of bovine colostrum are of special importance and require further detailed elucidation.     

Plasma vitamin A status in calves fed colostrum from cows that were fed vitamin A during late pregnancy

Calves are born vitamin A and β‐carotene deficient and the β‐carotene conversion to vitamin A is limited. Colostrum, contains relatively large amounts of vitamin A and β‐carotene and the retinol and β‐carotene status of calves can be normalized with colostrum consumption. We studied whether vitamin A supplementation of cows during late gestation (dry period) increases cow plasma retinol concentrations, the retinol content of first colostrum, and the plasma vitamin A status of calves during their first month of life. Both plasma and colostrum retinol concentrations were higher in vitamin A supplemented cows than in non‐supplemented cows. In calves that were for 5 days fed colostrum (milk) from vitamin A‐supplemented cows and then mature milk, plasma retinol concentrations were higher from 14 to 30 days after birth than in calves that were fed colostrum (milk) from cows that were not vitamin A supplemented. The study shows that vitamin A supplementation of cows during the dry period can improve the vitamin A status of their calves up to 1 month, if calves ingest their colostrum/milk for up to 5 days.     

奶牛初乳与常乳中营养成分和免疫物质的特征

初乳是奶牛产后24 h内的乳汁,为犊牛提供天然免疫和早期生长的能量来源,且初乳在医疗保健领域也具有一定的研究价值。初乳在产后一段时间内的物质成分会发生较大的变化,与常乳形成明显的差异。本文对比分析了初乳和常乳中营养物质、免疫活性物质、生长因子以及酶的含量差异,直观地展现了初乳中不同物质的变化过程,针对性地为初乳和常乳的加工制作提供思路,为特异性地开发初乳资源,提升初乳的利用率给出参考依据。     

高原犊牦牛培育的研究现状与进展

作者阐述了高原犊牦牛培育的研究现状,通过对近年关于牦牛围产期、初乳饲喂、放牧饲养、早期出栏、早期断奶与代乳料、益生素使用等方面研究文献的总结,结合高原地区实际情况,提出建立高原犊牦牛培育系统研究的需求。     

Evaluation of the transfer of immunoglobulin from colostrum anaerobic fermentation (colostrum silage) to newborn calves

Colostrum silage is an anaerobic fermentation methodology of excess farm colostrum used to conserve and provide as milk replacement for calves. The present study aimed to evaluate the levels of immunoglobulins present in bovine colostrum silage and its absorption by newborn calves. The concentration of immunoglobulins was determined in fresh colostrum and colostrum silage stored for 12 months. The absorption of immunoglobulins by calves was assessed immediately after birth and 24 h after colostrum silage intake. The immunoglobulin levels were evaluated by ELISA. The results highlighted that colostrum silage kept similar levels of immunoglobulins as the ones in colostrum in natura, and can be transferred to newborn calves with similar amounts to calves fed with colostrum in natura. It is concluded that colostrum silage keeps viable immunoglobulins, and is able to transfer passive immunity to newborn calves.     

Activities of gamma-glutamyltransferase, alkaline phosphatase and aspartate-aminotransferase in colostrum, milk and blood plasma of calves fed first colostrum at 0-2, 6-7, 12-13 and 24-25 h after birth

Enzyme activities of gamma-glutamyltransferase (gamma-GT), alkaline phosphatase (AP) and aspartate-aminotransferase (AST) were measured from birth to the age of 28 days in calves which were fed colostrum at 0-2, 6-7, 12-13, or 24-25 h after birth. Enzyme activities were also measured in colostrum (first to fifth milking) and in mature milk. Activities were highest in the first colostrum milking and decreased to the lowest activities in mature milk. Plasma gamma-GT activity transiently increased after first colostrum intake and was greater in calves fed first colostrum within less than 6-7 h than in those fed first colostrum later than 12 h after birth. Activity of gamma-GT reflected the absorption of colostral gamma-GT, which decreased with time after birth. The AP activity transiently increased after colostrum intake and was higher in calves fed colostrum within the first 12 h of life than in those fed later after birth. The transient rise of plasma AP activity also indicated absorption of colostral AP, although endogenous sources of AP could not be excluded. The activity of AST also transiently increased after colostrum intake but there was no association with time of first colostrum feeding, indicating that the rise of plasma AST activity was the consequence of enhanced endogenous production and was independent of colostrum intake. In conclusion, there are different causes leading to postnatal changes in enzyme activities.     

Preparing Holstein steer calves for the feedlot.

It is increasingly common to raise Holstein steer calves for entry to feedlot production systems rather than more traditional milk-fed veal production systems. Providing adequate nutritional support for the maintenance and growth of Holstein calves is essential in preparing them for a commercial feedlot environment. In this article, the dietary requirements of preruminant calves are reviewed and examples of evaluating milk diets for Holstein calves are detailed. The importance of the transition between milk feeding and grain-forage diets is discussed. Aspects of disease prevention, such as coccidiosis control and colostrum feeding, are also discussed. The reader will gain practical tools to use in preventive medicine programs involving Holstein steers being prepared for commercial feedlots.     

Diarrhoea in dairy calves reduced by feeding colostrum from cows vaccinated with rotavirus

Forty-two dairy calves remained with their dams for two days after birth, and then were removed to a calf rearing shed. Calves were allocated to three groups for the next 14 days, and received twice daily either whole milk, whole milk with a 10 per cent supplement of pooled normal bovine colostrum or whole milk with 10 per cent supplement of colostrum from cows vaccinated with rotavirus. A natural outbreak of diarrhoea occurred, affecting 28 of the 42 calves. Feeding immune colostrum delayed the onset of diarrhoea, and reduced its incidence, duration and severity. Live weight gains were consequently improved. The group fed normal colostrum had diarrhoea intermediate in severity between that of control calves and those fed immune colostrum. The aetiology of the diarrhoea was complex, with calves excreting rotavirus, enteropathogenic Escherichia coli and cryptosporidia.     

Effect of passive immunity on the development of a protective immune response against bovine viral diarrhea virus in calves

OBJECTIVE: To determine whether passively acquired antibodies prevent development of a protective immune response to live virus in calves. ANIMALS: 18 calves. PROCEDURES: Calves were caught immediately after birth and tested free of bovine viral diarrhea virus (BVDV) and serum antibodies against BVDV. Within 48 hours, 12 calves were fed colostrum that contained antibodies against BVDV and 6 calves received BVDV antibody free milk replacer. Three milk replacer fed and 6 colostrum fed calves were exposed to virulent BVDV2-1373 at 2 to 5 weeks of life when passively acquired serum antibody titers were high. After serum antibody titers against BVDV had decayed to undetectable concentrations (at 7 to 9 months of age), the 3 remaining milk replacer fed calves, 6 colostrum fed calves previously exposed to BVDV2-1373, and 6 colostrum fed calves that had not been exposed to the virus were inoculated with BVDV2-1373. RESULTS: Passively acquired antibodies prevented clinical disease in inoculated colostrum fed calves at 2 to 5 weeks of life. Serum antibody titers did not increase in these calves following virus inoculation, and serum antibody titers decayed at the same rate as in noninoculated colostrum fed calves. Inoculated colostrum fed calves were still protected from clinical disease after serum antibody titers had decayed to nondetectable concentrations. Same age colostrum fed calves that had not been previously exposed to the virus were not protected. CONCLUSIONS AND CLINICAL RELEVANCE: A protective immune response was mounted in calves with passive immunity, but was not reflected by serum antibodies titers. This finding has implications for evaluating vaccine efficacy and immune status.