奶牛瘤胃酸中毒的诊断鉴别及防治

瘤胃酸中毒是由于过多饲喂谷类或多糖类饲料后,导致瘤胃内发酵异常,产生大量的乳酸,在临床上是以瘤胃液pH值降低、渗透压升高和瘤胃内微生物区系的改变等为主征的一种瘤胃消化机能紊乱性疾病。     

粗饲料长度对反刍动物的影响及物理有效纤维的测定方法

日粮中的粗纤维被认为是饲料中相对较难被动物消化利用的那一部分，尽管如此，粗纤维还是具有很多重要的生理功能。除了能提供能量及部分营养成分外，粗纤维还具有刺激咀嚼、胃肠蠕动、充实胃肠道和调节胃肠道微生物区系等作用，其中对动物的咀嚼和分泌唾液的刺激作用是非常重要的一面。维持瘤胃正常功能的作用主要表现在可以中和瘤胃发酵产生的有机酸，保持瘤胃的酸碱度和瘤胃微生物的活性，因此当日粮缺乏纤维时，动物的唾液分泌量将会减少，造成瘤胃内环境发生变化，主要是降低瘤胃pH值，改变胃肠道内微生物种类及数量以及瘤胃发酵模式，长此以往，会对动物的健康造成损害从而影响生产。     

瘤胃原虫对反刍动物的影响

反刍动物瘤胃内栖生着大量微生物，主要包括细菌、真菌和原虫，它们对于饲料在瘤胃内的降解起着十分重要的作用。本文主要论述了瘤胃内原虫对瘤胃营养物质代谢的影响。研究发现，去原虫后，瘤胃发酵类型发生改变，丙酸产量增加，甲烷产量减少。并且去原虫后，可以改变淀粉及蛋白质的消化，有利于改善家畜的生产性能。     

反刍动物瘤胃臌气的治疗

瘤胃臌气也称瘤胃臌胀、肚胀、气胀，是牛、羊等反刍动物采食了已发酵的饲料，在瘤胃内微生物的作用下异常发酵，产生大量气体，引起瘤胃迅速膨胀的疾病。     

瘤胃稀释率对蛋白质发酵和微生物生长效率的影响

采用连续培养系统的12个发酵罐进行2次培养试验,研究瘤胃稀释率(D)对于活体外蛋白质发酵和微生物生长效率的影响。6个瘤胃稀释率分别为每小时发酵液流出量占发酵罐体积的0.025,0.050,0.075,0.100,0.150和0.200倍。以大豆提取蛋白为试验日粮,随着D的提高,饲料干物质、有机物质和粗蛋白真消化率均呈二次曲线趋势下降。提高D导致发酵液pH值提高,NH#-3和挥发性脂肪酸（VFA）浓度下降。每个VFA摩尔比例随D的改变而变化,并表现出蛋白质发酵特征。微生物N日产生量和微生物生长效率随D的提高而显著提高。蛋白质发酵的最大微生物生长效率为每千克可消化有机物合成微生物N 71.4g,其相对应的D为0.207/h。二次曲线模型适合于描述微生物生长效率。     

赖氨酸水平可引起瘤胃微生物代谢途径变化

正中国农业科学院饲料研究所反刍动物饲料创新团队对犊牛日粮氨基酸需要量和平衡模式进行了系统性研究,发现赖氨酸缺乏对母犊牛瘤胃发酵功能和微生物区系组成具有调控作用,为反刍动物绿色养殖及饲料生产中合理使用氨基酸,降低日粮蛋白质水平提供了理论依据。相关研究成果在线发表于《应用微生物学与生物技术(Applied Microbiology and Biotechnology)》。     

瘤胃发酵过程及其调控

综述了各饲料养分在瘤胃中发酵的过程和类型,以及瘤胃调控的理由和目标,并从改变日粮成分和比例、日粮的加工处理、利用添加剂和利用生物技术四个方面对瘤胃调控进行了详细论述.旨在为粗饲料加工提供理论依据,以提高反刍动物的生产效率.     

生物技术在提高秸秆饲料利用率上的研究与应用

论述了我国秸秆资源的利用现状及存在的问题,介绍了利用青贮、酶制剂、微生物处理、加曲(混菌)发酵等生物技术处理秸秆以提高饲料利用率的研究进展。     

牛瘤胃臌胀的防治浅析

<正>牛的瘤胃鼓胀也称胀肚病,胀气病。该病因前胃神经反应性降低,收缩力减弱,一次性采食大量易发酵的饲料,如三叶草、新鲜苜蓿、豆科植物,块根植物等,在瘤胃内微生物的作用下,异常发酵,大量产气,从而引起瘤胃、网胃急剧膨胀,导致呼吸与血液循环障碍,甚至窒息的一种疾病。此病多为原发,也可继发于某些前胃疾病。笔者就多年来治疗牛瘤胃臌胀的经验对该病作一简介。一、病因原发性瘤胃臌胀多发生于过量采食容易发酵的青绿饲料,如     

反刍动物瘤胃臌气的治疗

瘤胃臌气也称瘤胃臌胀、肚胀、气胀,是牛、羊等反刍动物采食了易发酵的饲料,在瘤胃内微生物的作用下异常发酵,产生大量气体,引起瘤胃迅速膨胀的疾病.     

提高反刍家畜对尿素的利用率

反刍家畜瘤胃微生物利用尿素合成的微生物蛋白质 ,能被家畜自身消化、吸收、利用。因此给反刍家畜饲喂尿素可以节省蛋白质饲料、降低饲料成本 ,能提高家畜的生产性能。但如果尿素饲喂不当 ,会降低其利用率。本文论述了影响尿素利用率的因素、尿素的饲喂方法及应注意的问题     

Direct-fed microbes: A tool for improving the utilization of low quality roughages in ruminants

For many years, ruminant nutritionists and microbiologists have been interested in manipulating the microbial ecosystem of the rumen to improve production efficiency of different ruminant species. Removal and restriction of antibiotics subtherapeutic uses from ruminant diets has amplified interest in improving nutrient utilization and animal performance and search for more safe alternatives. Some bacterial and fungal microorganisms as a direct-fed microbial(DFM) can be the most suitable solutions. Microorganisms that are commonly used in DFM for ruminants may be classified mainly as lactic acid producing bacteria(LAB), lactic acid utilizing bacteria(LUB), or other microorganism's species like Lactobacillus, Bifidobacterium, Enterococcus, Streptococcus, Bacillus, Propionibacterium, Megasphaera elsdenii and Prevotellabryantii, in addition to some fungal species of yeast such as Saccharomyces and Aspergillus. A definitive mode of action for bacterial or fungal DFM has not been established; although a variety of mechanisms have been suggested. Bacterial DFM potentially moderate rumen conditions, and improve weight gain and feed efficiency. Fungal DFM may reduce harmful oxygen from the rumen, prevent excess lactate production, increase feed digestibility, and alter rumen fermentation patterns. DFM may also compete with and inhibit the growth of pathogens, immune system modulation, and modulate microbial balance in the gastrointestinal tract. Improved dry matter intake, milk yield, fat corrected milk yield and milk fat content were obtained with DFM administration. However, the response to DFM is not constant; depending on dosages, feeding times and frequencies, and strains of DFM. Nonetheless, recent studies have supported the positive effects of DFM on ruminant performance.     

反刍动物饲料产品和动物源性饲料产品中牛羊源成分检测

利用聚合酶链式反应法(PCR法)对反刍动物饲料产品(预混料、精料补充料、全价配合料等)和动物源性饲料产品(鱼粉、肉粉等)共计350个样品进行了牛羊源成分检测.结果表明,有3个样品检出牛和/或羊源性成分,牛羊源性成分检出率0.86%.其中,反刍动物饲料产品310批次,牛羊源性成分检出率为0.97%;动物源性饲料产品40批次,均未检出牛羊源性成分.     

酵母菌种的筛选及其对反刍动物的影响

随着酵母类饲料添加剂在反刍动物中应用的日益增加,酵母菌对瘤胃作用的生物学机理及酵母菌与瘤胃内微生物的相互作用逐渐成为研究热点。文章针对目前国内外新型酵母菌种的筛选工作,在影响新型酵母菌筛选的因素,如何利用分子生物学技术选择新型酵母菌种、以及新型酵母对反刍动物的作用机理等方面进行了分析,为进一步研究提供理论依据。     

Protection of cattle against rinderpest with vaccinia virus recombinants expressing the HA or F gene

Rinderpest is a highly contagious ruminant viral disease manifested by a rapid course and greater than 90% mortality. Infectious vaccinia virus recombinants were constructed that express either the hemagglutinin or the fusion gene of rinderpest virus. All cattle vaccinated with either recombinant or with the combined recombinants produced neutralizing antibodies against rinderpest virus and were protected against the disease when challenged with more than 1000 times the lethal dose of the virus.     

烟酸与反刍动物营养物质关系研究进展

笔者就烟酸对反刍动物营养物质研究概况进行了阐述,简要说明烟酸的理化性质、与反刍动物3大类营养物质之间的关系、以及其在反刍动物生产中的应用等,以期能为烟酸在反刍动物上的应用提供理论支持。     

延胡索酸及其盐作为反刍动物饲料添加剂的研究进展

延胡索酸及其盐在饲料添加剂中可作为一种酸化剂、抗应激剂和防腐剂,目前己经在单胃动物饲料中获得了广泛应用。对于反刍动物来说,延胡索酸及其盐可以作为替代莫能菌素等抗生素的物质,在反刍动物的体内和体外研究中表现出一定的甲烷抑制潜能,同时对反刍动物生产性能产生有利影响。文章主要综述了延胡索酸及其盐对反刍动物瘤胃发酵和生产性能的影响。     

Postmodern management of starchy grains for ruminants: A barley grain perspective

Maintaining optimal rumen conditions faces many challenges when feeding ruminants barley grain (BG). This is because >90% of BG endosperm can be rapidly degraded to acids, peptides, and ammonia, whereas corn grain is degraded more slowly and only by 35–50%. Excessive processing may reduce and maintain rumen pH under 5.8, causing prolonged subacute rumen acidosis (SARA) and suppressed immunity. Steam-rolling and grinding are two main global processing methods for BG. It is criticized how inaccurately inherited focus on processing rather than accurate dietary inclusion rate of BG has compromised rumen and ruminant health. Overemphasis on processing methods and quality control have kept producers far from granting deserving thoughts into safe BG inclusion rates under different feeding programs. A major philosophy for steam processing of hard grains (e.g., corn and sorghum) is to increase rumen starch and protein fermentation extent, whereas in softer grains (e.g., BG) a primary goal is totally different, being instead to control and decelerate fermentation shortly post-feeding. These aims must be profoundly appreciated to maximize microbial mass yield and overall VFA production with minimized risks from SARA and immune dysfunction. Optimum dietary inclusion rates and physical form of BG in relation to physiological stage and lactation performance are discussed. In practice, challenges usually arise from too-complex outlooks. Main challenges faced by ruminant industries will not be to alleviate or attenuate disorders such as SARA and pro-inflammatory reactions, but instead to prevent and minimize their occurrence. A perturbing trend in modern ruminant industries has been creating health problems by improper feeding strategies and investing time and other resources to overcome such problems. Optimum processing techniques and feeding strategies of BG should aim to minimize metabolic complexities, and improve economics by more effective prognosis, diagnosis, and treatment. Effectual ruminant management is in controlled microbial cereal starch utilization in the rumen. Rumen is a foremost target to improve starch and BG assimilation in postmodern ruminants.     

提高饲料过瘤胃蛋白率的技术措施

过瘤胃蛋白指饲料中未被瘤胃微生物降解而直接进入小肠的蛋白质,是反刍动物吸收氨基酸的重要来源。通过降低饲料蛋白质在瘤胃内的降解率,提高蛋白质的过瘤胃率,增加氮在体内的沉积,可提高优质蛋白质饲料的利用率,从而提高反刍动物的生产性能。国内外对提高饲料过瘤胃蛋白进行了大量的研究,包括各种热处理方法、化学方法和物理包被等,文章综述了提高饲料过瘤胃蛋白的技术措施及其在生产中的应用效果。     

中部四省反刍动物饲料发展趋势与对策研究——兼论“5个重要指标”的指导作用

以王加启(2011)提出的"决定我国奶业发展方向的5个重要指标"为指导,在大量调研的基础上,系统分析了中部四省(河南、湖北、湖南与江西)的社会发展概况、主要反刍动物饲养现状与发展趋势、天然牧草资源、秸秆资源与反刍动物工业饲料生产情况,指出了制约中部四省反刍动物发展的饲草因素。此外,还阐明了中部四省反刍动物饲料可持续发展的政策保障,提出了中部四省反刍动物饲料可持续发展的对策。本研究强调了反刍动物粗饲料与精饲料的同等地位以及饲料转化率的重要意义。