微生态制剂作用机制及对畜禽免疫功能的影响

微生态制剂在促进畜禽肠道功能及肠腔微生物区系稳态方面效果显著。肠道上皮及黏膜是机体有效防止外源性病原体侵入的第一道屏障,对于维护机体健康发挥重要作用。微生态制剂可以增强肠上皮细胞紧密连接及免疫物质的分泌,改善肠道黏膜屏障,维护机体健康。文章综述了微生态制剂对畜禽肠道的作用机制及其对畜禽免疫器官、免疫细胞及因子、肠道黏膜免疫功能的影响,以期为微生态制剂的研发及其在畜禽生产中的应用提供新思路。     

畜禽微生态制剂的研究进展及在猪鸡中的应用

随着现代养殖业的发展，畜禽微生态制剂在世界范围内越来越受到人们重视。本文系、统介绍了畜禽微生态的作用原理及其在生产上的应用。     

微生态制剂对蛋种鸡生产的影响

本文论述了微生态制剂的作用机理及其对蛋种鸡生产的影响。微生态制剂能改善畜禽肠道微生态环境,提高畜禽对养分的利用率,增强机体免疫力,在蛋种鸡生产中已经开始应用。     

乳酸菌对畜禽免疫功能的作用机理研究进展

<正>随着微生态学的崛起,在畜禽养殖业中微生态制剂成为饲料添加剂的重要组成部分。微生态制剂中通常以双歧杆菌和乳酸杆菌的应用最为广泛。畜禽服用乳酸菌后,不仅可以改善胃肠道菌群平衡[1,2],提高畜禽的成活     

微生态制剂在畜牧业生产中的应用研究展望

微生态制剂作为一种安全、绿色的新型饲料添加剂,已被广泛应用于畜牧业生产。综述了微生态制剂在畜禽养殖业中的应用研究进展,阐述了副拟杆菌作为下一代新型益生菌添加剂产品在畜牧业中的应用潜力,以期为研发新型畜禽用微生态制剂提供新思路。     

微生态制剂对产蛋后期肉种鸭产蛋率及蛋重的影响

微生态制剂在畜禽养殖中的应用日益广泛,微生态制剂在提高养殖动物生产性能、提升畜禽产品品质、改善畜禽舍生态环境等方面取得了广泛认可。本研究在产蛋后期肉种鸭日粮中添加微生态制剂．统计产蛋后期肉种鸭的产蛋数并计算产蛋率,随机称量蛋重。结果表明．在产蛋后期肉种鸭日粮中使用微生态制剂．对产蛋率有明显提升作用;并对蛋重无不良影响,符合孵化标准。     

不同微生态制剂对肉仔鸡生产性能的影响

应用有益微生物制成的微生态制剂，是近年发展起来的一种新型饲料添加剂。它具有调节畜禽肠道微生物群落，维持肠道菌群平衡，增强畜禽免疫力，提高畜禽生产性能，无毒副作用、无耐药性、无残留等特点。为了验证微生态制剂在肉鸡生产中的应用效果，本试验在日粮中添加不同种的微生态制剂后检测其对肉仔鸡生产性能的影响，为微生态制剂在肉仔鸡中应用提供依据。     

不同微生态制剂对肉仔鸡生产性能的影响

应用有益微生物制成的微生态制剂，是近年发展起来的一种新型饲料添加剂。它具有调节畜禽肠道微生物群落、维持肠道菌群平衡、增强畜禽免疫力、提高畜禽生产性能、无毒副作用、无耐药性、无残留等特点。为了验证微生态制剂在肉鸡生产中的应用效果，本试验在日粮中添加不同种的微生态制剂对肉仔鸡生产性能的影响，为微生态制剂在肉仔鸡中应用提供依据。     

纳豆菌微生态制剂的研究进展

纳豆菌是农业部批准的可用于饲料的微生态制剂之一。作为新兴的微生态制剂,纳豆菌有着多种益生功能,用于畜禽生产中能取得较好的饲喂效果,文章对纳豆菌的生物特性、作为微生态制剂的优越性及作用机理作了概括总结,并介绍了其在畜禽生产中的应用,最后对纳豆菌微生态制剂的发展作了展望。     

微生态制剂在畜牧业中的应用

微生态制剂是近年来新研发出的一种有助于畜禽生长,能够提高饲料报酬、预防畜禽疾病发生、辅助治疗各种畜禽疾病的绿色饲料添加剂,它在畜产品产量增长、质量提高等方面都发挥了积极的作用。本文以微生态制剂为研究对象,重点介绍了这种制剂的概念、分类、微生态制剂的作用机制,通过分析这种制剂在畜禽养殖过程中的应用效果对其进行深入研究,以期能够进一步提高这种制剂在畜牧业发展中的作用。     

Gordon memorial lecture. Poultry disease and public health

The development of the poultry industry and the consumption of poultry meat is traced over the past quarter of a century and related to the increased incidence of food poisoning in man. Factors affecting the spread of the main poultry pathogens which are of human significance are discussed. The pathogens considered are salmonella, campylobacter, staphylococci and clostridia. Various preventative measures are considered including rearing procedures for poultry, decontamination methods and education of the public. It is concluded that one of the most effective measures is irradiation of poultry and poultry products. The difficulties of introducing this control measure are recognised. It is concluded that more effective application of existing control methods would greatly reduce the hazards to public health.     

禽蛋和禽肉中兽药残留检测技术研究进展

随着我国家禽产业的规模不断扩大,兽药残留问题也更加严峻。兽药残留对人体与环境危害重大。现对目前禽蛋和禽肉中常见的兽药残留种类及最大残留限量进行综述,探讨了(超)高效液相色谱法、(超)高效液相色谱-质谱法、气相色谱-质谱法和免疫学检测法、分子印迹技术、生物芯片技术、生物传感器检测法在禽蛋和禽肉中的应用价值,以期为兽药残留检测和监管提供依据。     

家禽胚胎性别鉴定方法研究进展

在家禽生产中,孵化时蛋用禽希望雌性雏较多,而肉用禽却希望雄性雏较多,且在蛋用禽中,雄性雏的处理也需要花费很大的资金。因此在孵化时,如果可以尽早的鉴别出胚蛋的性别,不仅可以节约孵化时的花费,更可以节约废雏的处理费用。作者主要介绍了几种家禽早期胚胎性别鉴定的方法,以期为国内此方面的研究提供借鉴。     

好氧堆肥技术在畜禽粪污资源化利用中的研究进展

畜禽粪污处理是我国可持续发展进程的重要难题,关系到我国养殖行业的发展和美丽乡村的建设。本文梳理了当下国内畜禽粪污资源化现状、发展趋势和相关政策法规,对好氧堆肥和沼气发酵等畜禽粪污资源化处理方式、应用现状等进行全方位综合对比并明确其优缺点和发展前景,结果发现,利用好氧堆肥技术处理畜禽粪污更符合我国国情。同时分析国内外在堆肥机理、发酵工艺和设备等研究进展,系统整理了堆肥发酵过程中关键因素对其效果的影响,包括含水率、碳氮比、温度、pH值、通气量和微生物菌剂等,最后分析了畜禽粪污资源化过程面临的难题并提出建议。     

Poultry husbandry and animal health

Close interactions are existing between poultry husbandry and poultry health. The more housing systems and the environment of the animals can be controlled, the less the general risk of disorders in poultry flocks--especially of diseases which are caused by the introduction of microoganisms. Resulting deterimental effects will affect not only the animals themselves, but also pose a risk indirectly for humans via food originating from animals under production. Also, by keeping the risk of infections as low as possible, the use of therapeutics can be avoided. This will reduce the risk of residues in food of animal origin. In summary, with all probability open poultry husbandry systems, especially those including free range systems pose increased risks for poultry health and consequently for the quality of food originating from poultry production. At least, those systems require highest standards of biosecurity, defined as management, location, farm layout, cleaning and desinfection incl. pest control programs, immunization and specific veterinary monitoring concepts to prevent infections.     

Non-commercial poultry industries: surveys of backyard and gamefowl breeder flocks in the United States

The National Animal Health Monitoring System (NAHMS) Poultry '04 study was conducted to better describe non-commercial United States poultry populations, in particular, backyard and gamefowl breeder flocks. To estimate the density of backyard flocks in close proximity to commercial operations, a sample of 350 commercial poultry operations in 18 top poultry producing states was selected from the National Agricultural Statistics Service (NASS) list of poultry operations. A 1 mile radius circle was drawn around each operation, and door-to-door canvassing was conducted within these circles to enumerate premises with all species of birds. Premises with backyard poultry flocks completed a questionnaire focusing on bird health, bird movement, and biosecurity practices. A similar questionnaire, provided in both English and Spanish, was mailed to all members of State affiliates of the United Gamefowl Breeders Association (UGBA) as well as to members of State associations not affiliated with UGBA. An average of 29.4 residences was found within a 1 mile radius of commercial operations, of which 1.9 residences per circle had backyard poultry flocks. Gamefowl breeder flocks were larger, used more health care and biosecurity practices, and moved birds more frequently compared to backyard flocks.     

Antibiotic resistant coliform bacilli, isolated from freshly slaughtered poultry and from chilled poultry at retail outlets

Antibiotic resistance in coliforms isolated from poultry was investigated. Poultry carcases were examined immediately after slaughter or at retail outlets; the carcases were from the same processing plant and 100 were examined from each source. Approximately 85% of the total of 13,858 isolates examined were found to be resistant to at least one antibiotic. Highly significant differences were found in the levels of antibiotic resistance from the 2 sources; ampicillin, chloramphenicol, and sulphonamide resistance was found more frequently in isolates from poultry at retail, while resistance against streptomycin and neomycin occurred more frequently in isolates from poultry examined at slaughter. The data were insufficient to explain these changes. Transfer of resistance occurred less frequently in isolates from poultry at retail; in particular the transfer of resistance from coliforms other than Escherichia coli was found to be greatly reduced.     

浅析夏季畜禽养殖场恶臭污染及控制

随着畜牧业生产规模的扩大和集约化程度的提高,畜禽养殖场产生的恶臭所造成的危害已经引起人们的普遍关注。恶臭的发生具有明显的季节性。对于畜禽养殖场来讲,夏季的恶臭污染程度要高于其它时节。本文针对夏季恶臭发生的特点,提出了相应的控制措施。     

拷贝数变异在畜禽中的研究进展

拷贝数变异（copy number variation,CNV）具有多种形式的变异结构,在品种多样性、生物进化和疾病相关性等研究中起着重要作用,并具有片段长度大、覆盖范围广等特点。随着分子生物学的发展及DNA测序技术的日渐成熟,人们对遗传变异的研究不断向DNA分子水平深入,多态性标记在畜禽育种中已逐渐成为动物育种研究的趋势和主流。由于CNV对基因的调控和表达所造成的影响更为显著,因此,CNV在重要畜禽中的研究越来越多。目前,已检测出大量有关畜禽重要经济性状的基因序列变异,并有许多研究均表明CNV与动物的重要经济特征及疾病的发生有关。笔者主要通过参考国内外相关的研究报道,简述了CNV的相关研究背景、概念、突变机制,归纳总结了CNV对牛、羊、猪、鸡的经济性状、繁殖性状和疾病调控的影响,以期通过对这些重要畜禽的基因组学研究揭示其适应性遗传机理和表型性状差异的遗传基础,开发相应的分子遗传标记,为畜禽的标记辅助选育提供理论基础。     

CRISPR/Cas9技术在畜禽育种中的研究进展

利用传统方法在畜禽特定基因座上进行基因组修饰时,只能通过在体细胞中进行同源重组再经细胞核移植实现。传统同源重组方法的困难性和低效性阻碍了基因修饰在畜禽遗传育种中的广泛应用。近年来,位点特异性核酸内切酶的发现为靶向基因修饰提供了一条更直接的途径,主要由于这些酶能直接在DNA序列上进行一步式的基因编辑。成簇规律间隔短回文重复序列/Cas关联蛋白9(clustered regularly interspersed short palindromic repeat/CRISPR associated protein 9,CRISPR/Cas9)是一种RNA导向的DNA内切酶,精准定位于特定的靶位点,高效完成RNA导向的DNA识别及编辑。CRISPR/Cas9技术作为精准而强大的第3代基因组编辑工具,已经成功应用于猪、牛、山羊、绵羊和鸡上,这些CRISPR/Cas9基因编辑畜禽可作为研究人或畜禽生理和病理的生物模型、生产功能性蛋白质的生物反应器或器官移植的供体。特别是在畜禽生产方面,CRISPR/Cas9基因编辑可用于改善生产遗传特性及畜产品质量,提高畜禽对疾病的抵抗力。作者对当前畜禽中特定位点基因组修饰的CRISPR/Cas9技术的原理及基因组编辑在畜禽育种中应用的最新进展进行了综述,以期为推进CRISPR/Cas9技术在畜禽育种中的研究提供参考。