直接饲喂微生物在奶牛生产中的研究进展

本文就直接饲喂微生物（direct-fed microbial,DFM）作用机理和对奶牛的生产性能的影响作了论述,并就今后的发展趋势作了探讨。     

直接饲喂微生物对奶牛瘤胃发酵和肠道的影响

直接饲喂微生物(DFM)能够提高奶牛的日增重和饲料效率,增加奶牛的产奶量,改善犊牛的健康状况。然而其作用模式不是很明确。本文对目前应用在奶牛养殖方面直接饲喂微生物的种类及其与瘤胃和肠道的关系及作用模式进行综述。     

直接饲喂微生物在反刍动物生产上的应用

直接饲喂微生物（DFM）能提高育肥牛日增重和饲料利用率，提高奶牛泌乳量，改善幼龄反刍动物的健康状况和生产成绩。然而，DFM的作用很不稳定，其作用模式不明。文中主要介绍了DFM对反刍动物健康和生产性能的影响，讨论了其潜在的作用机理。并对有待于继续研究的问题进行了探讨。     

直接饲喂微生物对反刍动物的影响

<正>瘤胃的微生态系统是一个多态性和竞争性的环境,也是一个动态平衡的体系。多年来营养学家和微生物学家对其进行了大量的研究,旨在通过调控瘤胃微生态系统来提高反刍动物的生产效率以及预防某     

直接饲喂微生物在反刍动物生产上的应用

直接饲喂微生物（direct-fed microbials,DFM）或者益生菌（probiotic）是纯天然产品。近几年来给高产泌乳奶牛直接饲喂微生物的实践正逐渐增加,普遍使用的直接饲喂微生物是酵母和酵母培养物。然而给奶牛饲喂酵母产品的研究结果各不相同,在提高干物质采食量、增加牛乳产量和乳成分上的效果也有显著差异。乳牛的泌乳时期、饲喂类型、饲喂方式和精粗比都会影响酵母和酵母培养物的饲喂效果。     

直接饲喂微生物对沙门氏杆菌的另一个挑战

几年前,Billy Hargis的家禽研究实验室发现了如何开发能够通过肉鸡和火鸡的饮水防止家禽抗沙门氏菌感染的益生菌——也称为直接饲喂型微生物（direct-fedMicrobials,DFMs）。由他们开发的其中一个DFM产品名叫FM-B11,该产品已授权给一家初创公司,随后被取FloraMax商品名的产品。但是,有一点是明确无疑的,即进行下一阶段的开发是必要的。     

直接饲喂微生物对荷斯坦奶牛的生产性能、日粮消化率和瘤胃特征的影响

美国明尼苏达大学Raeth-Knight通过直接饲喂微生物（DFM）产品（包含嗜酸乳酸杆菌和费氏丙酸杆菌），对泌乳中期的荷斯坦奶牛生产性能、营养素消化率和瘤胃发酵率的影响试验。试验牛分为3种不同的日粮处理组：     

有效微生物微贮稻草粉生物饲料饲喂奶牛试验

承蒙省饲料工业办公室牵线、湖南长沙依恩实业有限公司提供的经益阳市生物工程研究所分离、制作和有效微生物秸杆饲料发酵的研究,取得了一定的成绩。为将研究所取得的成果应用于生产,在生产中去检验,并生产出了一定数量的有效微生物菌液(每毫升含菌数1亿个以上)和有效微生物微贮稻草粉生物饲料(色泽金黄,气     

饲用微生物在反刍动物中应用的研究进展

本文旨在讨论饲用微生物的分类,调控瘤胃的作用机制,以及在反刍动物生产中的应用现状,阐述饲用微生物在反刍动物应用的安全性和促进反刍动物生产性能的有效性,为反刍动物的健康生产提供理论指导和现实依据。     

奶牛乳腺炎金黄色葡萄球菌疫苗研究进展

奶牛乳腺炎是由多种因素引起的严重影响奶牛业发展的重要疾病,金黄色葡萄球菌是引起奶牛乳腺炎的主要病原,至今还没有有效的方法预防金黄色葡萄球菌所致的乳腺炎.虽然已经研制了许多金黄色葡萄球茵疫苗,但是试验表明,这些疫苗的免疫效果并不理想,因此仍将继续搜索有效疫苗.目前,亚单位疫苗和DNA疫苗成为研究热点,研究集中在金黄色葡萄球茵的表面抗原上.利用金黄色葡萄球茵分泌的免疫原性蛋白而制成的疫苗可能具有高免疫效力,这些抗原将成为高效疫苗的候选者.同时,应用低毒的金黄色葡萄球菌突变株,也可能成为预防乳房炎的一种新工具.     

Effect of Yeast Culture and Direct-Fed Microbes on the Growth Performance and Rumen Fermentation of Weaner Lambs

The effects of yeast culture and directfed microbes on the growth performance of weaner lambs was examined.Thirty-two Hu lambs with inihtial weight of 22.20 ( + 0.75 ) kg were randomly assigned to one ...     

奶牛早期妊娠诊断技术的研究进展

高效准确的早期妊娠诊断,可以缩短母牛的产犊间隔,从而达到提高母牛繁殖效率的目的。家畜早期妊娠诊断方法的研究具有悠久的历史,从原始的外部观察法到目前应用最广泛且最直接的直肠检查法,再到后期发展起来的超声波检查法以及近年来研究比较多的易于商业化的间接检测法。本文对在生产中具有实际应用效果且具有一定发展前景的早期妊娠诊断技术应用现状进行了综述。     

奶牛子宫内膜炎研究进展

近年我国奶牛业发展十分迅速，然而不孕症对奶牛养殖业的发展有着重要的影响。大量资料表明，不孕症占奶牛疾病的20％～30％，子宫内膜炎占不孕症的40％～60％。据资料报道，美国每年有12．19％的奶牛是由于不孕症或繁殖疾病而被淘汰，占淘汰母牛的52．37％，每年因不孕症损失高达2．7亿美元；俄罗斯患不孕症奶牛占适龄母牛的10％，而子宫内膜炎在不孕症中所占比例最大；英国奶牛子宫内膜炎占不孕症的95％；北京农业大学对北京、南京、上海等16城市调查，子宫内膜炎占不孕奶牛的68．34％；1984-1988年中国农业科学院中兽医研究所对10个城市30个奶牛场的10495头适龄母牛做了调查，产后患子宫内膜炎的有2107头，发病率为20．08％；浙江省金华市黄昌发等调查了新狮乡1060头奶牛，有640头患子宫内膜炎，发病率达60％以上；江苏省农科院畜牧兽医研究所调查了徐州、无锡、泰州、连云港等11个奶牛场的2910头分娩奶牛，患子宫内膜炎的852头，占29．3％。国内外资料表明，子宫内膜炎病是引起奶牛不孕的主要原因。     

奶牛真胃变位的研究进展

随着奶牛饲养集约化的程度越来越高,奶牛真胃变位的发生和死亡率也呈上升趋势,造成日渐严重的经济损失,对奶牛业健康发展构成了严重的威胁,因此对奶牛真胃变位的病因及防治方法探讨很有必要.文章就近年来有关奶牛真胃变位的病因和发病机理、临床症状、诊断及治疗方法、研究进展进行综述.     

奶牛乳房炎诊断技术的研究进展

奶牛乳房炎是影响奶牛生产的主要疾病之一。病原菌的免疫抑制以及日趋严重的耐药性,致使乳房炎的发病率增高且治愈困难,给世界奶牛养殖业造成了巨大的经济损失。实践表明,疾病的诊断是疾病病因和治疗之间最重要的一步。经济、快速、可靠的诊断工具是乳房健康管理的基础。本文主要论述了奶牛乳房炎不同诊断方法的优缺点以及新兴诊断技术的研究进展。     

奶牛子宫内膜炎研究进展

子宫内膜炎是奶牛中一种常见的产科疾病,它可引起奶牛不孕,给奶牛养殖带来严重经济损失。引起奶牛子宫内膜炎的主要原因可概括为理化性和生物性二类,病原菌的侵入可通过上行性感染和下行性感染的途径造成子宫炎的发生,主要致病菌有葡萄球菌、大肠埃希菌、链球菌等。直肠检查和内窥镜检查仍是奶牛子宫内膜炎的常规的诊断方法,但仍有待于探索简便准确的新诊断方法。恢复子宫张力,促进子宫血液循环和炎性分泌物排出,抑制或消除子宫内感染病菌是子宫内膜炎的主要治疗原则,常用的治疗方法有冲洗子宫,全身疗法,抗生素和激素疗法以及中药治疗等。创建新的治疗和诊断方法,开发疗效好的药物将是提高奶牛子宫内膜炎诊疗水平的努力方向。     

Study on the Microbial Fermentation Feed Formula and Its Turning Process of Dairy Cows

This experiment was conducted to study the effects of eight microbial fermentation feed formulas and the different turning processes on the yeast viable bacterial number and three kinds of nutritional active substance contents to determine the optimal formula and its turning process.Nine kinds of local agricultural products,such as wheat bran,rice bran,cottonseed meal and corn flour,were used as fermentation materials and eight different formulas were designed by mixture design of DPS.Saccharomyces cerevisiae BC,XR4 and Bacillus subtilis A15 were mixed by 2:2:1 and inoculated in the eight formulas to conduct solid state fermentation.The yeast viable bacterial number and the content of mannan,β-glucan and polypeptide were measured to screen the optimal formula.Basing on the optimal formula,the turning process experiment was conducted.There were three groups:Control group,experimental group 1 and 2.The control group was without turning process,while the feed in the experimental group 1 was turned once and the feed in the experimental group 2 was turned twice.The material temperature,yeast viable bacterial number and three kinds of nutritional active substance contents were measured to determine the optimal turning process.The results showed that:① Formula 8 was the optimized formula which consisted of 8.62% wheat bran,5.85% vinegar residue,20.89% rice bran,12.55% cottonseed meal,11.35% corn flour,7.31% corn bran,1.10% corn residue,25.36% sugar residue,5.35% corn germ meal,1.02% (NH₄)₂SO₄,0.50% KH₂PO₄ and 0.10% MgSO₄.② The best turning process of formula 8 was turning twice during the solid state fermentation.When the material temperature reached 35℃,the first turning was conducted and then when the temperature reached 42℃,the material would be turned again.After that the material continued fermenting until the end.Its optimal indexes were viable bacterial number was 4×10⁵ CFU/g,and the content of mannan,β-glucan and polypeptides were 41.28 mg/100 mg,87.06 mg/100 mg and 10.32 μg/100 mg,respectively.Its improved by 100.00%,3.90%,4.89% and 1.67% separately than the control group and improved by 33.33%,3.07%,3.31% and 0.88% comparing with the experimental group 1.     

Performance and cost-benefit improvements following supplementation with a combination of direct-fed microbials and enzymes to broiler chickens raised with or without ionophores

Increased resistance and loss of sensitivity to traditional anticoccidial agents, as well as interest in antibiotic-free rearing programs, has increased the interest in alternative control measures. Therefore, this study aimed to assess the effect of a DFM (direct fed microbial)/multi-enzyme product (DFM+XAP, providing 2,000 U/kg xylanase, 200 U/kg amylase, 4,000 U/kg protease and 75,000 cfu/g DFM) on broiler performance and profitability under 2 anticoccidial strategies (vaccination and traditional ionophore therapy). The study diets were 1) a nutritionally adequate control based on corn/soy/DDGS (PC), 2) a negative control reduced in energy and amino acids (NC), and 3) NC+DFM+XAP. Diets were divided into 2 subgroups, receiving either ionophores from 0 to 43 d (salinomycin 60 g/t) or a coccidial vaccine (Coccivac B) (6 treatments, n = 8, 50 male birds/n). Performance was recorded on d 22, 35 and 43. The net value of DFM+XAP inclusion was determined for all treatments. At d 43 reduced BWG and highest FCR were seen in NC birds, regardless of coccidiosis control (P < 0.05). Adding DFM+XAP significantly improved BWG and FCR by 5% (2,087 vs. 1,991 g/bird) and 6% (1.803 vs. 1.906), respectively. In birds receiving vaccine (P < 0.05), resulting in BWG (2,125 g/bird) and FCR (1.772) not statistically different to birds fed PC diets. Across anticoccidial strategies, adding DFM+XAP resulted in 3% BWG improvement (P < 0.05) as compared to NC. The net value of DFM+XAP addition, compared to PC, was $15.15/ton feed in vaccinated birds and $14.71 in those treated with ionophores. In conclusion, the addition of DFM+XAP to broiler diets significantly improved performance and profitability, regardless of coccidiosis control program, though response was likely to be greater in vaccinated birds.