后生元的益生机制及其在畜禽生产中应用的研究进展

随着益生菌、益生元和合生元的深入研究，后生元随之诞生并迅速成为研究热点。后生元的稳定性和安全性等特质明显优于益生菌，它不仅在药品和食物领域被广泛应用，在畜禽应用上也有不少的研究。研究表明后生元对畜禽具有多种有益效应，本文将就后生元定义、特点和组成、益生机制及其在畜禽生产上的应用进行综述。     

后生元的益生机制及其在动物生产中的应用前景

后生元是指对宿主健康有益的无生命微生物体和/或其代谢产物的总称,其主要成分包括磷壁酸、肽聚糖、有机酸、细菌素、胞外多糖和神经递质类物质等,这些物质具有调节肠道菌群平衡、增强肠粘膜屏障和免疫功能以及调节肠-脑轴等益生功能。相较于益生菌,后生元的化学结构明确、安全性更高、稳定性更强以及耐贮存等,因而逐渐被应用于医学和食品等领域,对其作用机制的研究也已成为热门。本文概述了后生元的定义、主要活性成分及益生机制研究进展,并展望其在动物生产上的应用前景。     

后生素：一类具有潜力的新型饲料添加剂

在益生菌领域,后生素是近些年兴起的一个研究热点,主要是灭活菌体、细菌的代谢产物以及菌体死亡裂解的细胞组分。目前关于后生素的相关研究和应用报道较少,文章主要对后生素的概念、生物学功能以及在畜牧生产中的应用进行综述,旨在为后生素作为新型饲料添加剂提供参考。     

我国益生乳酸菌及益生发酵乳研究开发现状及发展对策

乳酸菌(Lactic acid bacteria)是指能发酵碳水化合物产生50%以上乳酸的一类细菌的总称.联合国粮农组织与世界卫生组织(2001)对益生菌的最新定义是:通过摄取适当的量、对食用者的身体健康能发挥有效作用的活性微生物.国际营养学界普遍认可的定义是:益生菌是一种对人体有益的细菌,可直接作为食品添加剂服用,以维持肠道菌群的平衡.英国福勒博士(RovFuller)将益生菌定义为:益生菌是额外补充的活性微生物,能改善肠道菌群的平衡而对宿主的健康有益.由此可见,乳酸菌和益生菌不是一个概念,不是所有的乳酸菌都可以称为益生菌,或用做益生菌及其产品.……     

家禽胚蛋注射技术的应用研究(综述)——益生菌和益生元篇

益生菌可以是一种活菌制剂,也可以是细菌的代谢产物,它可以通过改变或重建动物肠道微生物菌群的组成来提高宿主的健康水平。益生元是植物中不能被宿主(动物)体内的酶分解的非淀粉多糖,能通过选择性刺激动物肠道微生物菌群的生长与活性对宿主产生有益的影响,从而改善宿主的健康水平。益生菌和益生元已经在畜牧生产中得到广泛的应用,一般经口补给,而胚胎供应或将成为给家禽添加益生菌或益生元的新途径,扩展其在动物保健方面的新功能。     

食品生产用动物及其健康关乎人类健康

正益生元的概念相对较新,不易消化的食物成分(如不能消化的低聚糖)可被一种或多种对肠道生理具有益作用的细菌选择性发酵,一些益生元可选择性地刺激肠道中内源乳酸菌和双歧杆菌的生长,增加益生菌数量,从而改善宿主健康。如果特定有益菌不存在,益生元就没有用处。同样,如果环境不利,活菌也不会产生效力。最近提出了共生概念,即同时含有益生元和益生菌属性的食物才是有益健康的功能食品。1益生菌和益生元能够改善动物健康、生产性     

后生元的功效及其在动物养殖中的应用研究进展

后生元是指对宿主健康有益的无生命微生物和/或其他成分的制剂，由于具有明显的益生功能及无生命微生物的特点，不论是生产还是应用都有巨大的市场前景。文章从后生元的定义、作用机理及常用后生元在动物养殖中的应用现状及应用前景等进行论述。     

后生素对肠道屏障的影响

肠道担负着重要的屏障功能，该屏障可以有效抵御致病菌和有毒有害物质的侵染。肠道的完整性直接影响机体的健康。后生素是近年来益生菌领域研究的新生长点，是指能够对机体起到有效健康的灭活益生菌及其代谢物。文章综述了后生素与肠道屏障健康的关系及其对机体肠道屏障的研究进展，为其在畜牧业中的应用提供一定参考。     

合益素对肉仔鸡肠道形态和体液免疫反应的影响

益生菌和益生元的组合被定义为合益素(Synbiotic).益生菌是活的微生物,已被用来维持宿主动物的正常菌群以提高动物生产性能,主要作用是增强肠黏膜对不良微生物的屏障作用(Fioramonti等,2003),刺激抗原特异性和非特异性免疫反应.益生元是一种膳食补充剂,通过选择性地刺激一种或几种菌落中细菌增长或活动,从而改善宿主健康"(Gibson和roberfroid,1995).已报告合益素对健康有许多益处,如抗菌、抗癌、免疫调节、止泻、抗过敏、降血脂、解毒、降低血糖活性等,还可以提高矿物质吸收和平衡,而且可能有抗骨质疏松作用(Zubillaga等,2001;Holzapfel和Schillinger,2002;Slizewska等,2010).     

微生态制剂的特点和应用

微生态制剂又称为微生物饲料添加剂，主要包括益生菌。益生元、合生元三类制剂。益生菌是活菌；益生元是一类化学物质，不能被宿主消化吸收，也不能被肠道有害菌利用，只能被有益微生物选择性地吸收利用或能促进有益菌的活性或繁殖；合生元为益生菌和益生元按一定比例结合的生物制剂,能同时发挥二者的共同作用。     

乳源性生物活性肽研究进展

乳源性生物活性肽具有营养作用，可作为生理功能的重要调节剂。本文综述近年来研究较多的几类乳源性生物活性肽的序列结构及其生物功效，并对其在乳品和医药工业中的应用前景进行展望。     

生物活性肽的生理作用及其在畜禽生产中的应用

随着各种具有生物活性的短肽的不断发现 ,其研究和开发日益受到各国科学家的关注。其可作为营养物质直接用于合成体蛋白及螯合和运输 Ca2 等矿物质 ,使矿物质的吸收利用率提高。免疫肽类则能刺激机体淋巴细胞的增殖和增强巨噬细胞的吞噬能力 ,从而增强机体的免疫力。具有抗氧化和调味作用的肽类可作为天然防腐剂代替化学合成产品以提高饲料品质。生物活性肽在畜禽日粮中的应用效果也证实了其可增进动物健康、促进畜禽生长发育及改善畜产品品质 ,在反刍动物则成为瘤胃微生物氮素营养研究新生长点。因此生物活性肽有广阔的研究和应用前景。     

蝇蛆的营养特性及其在畜禽生产中的应用研究进展

蝇蛆繁殖能力强、生长周期短、养殖成本低,其粗蛋白质、不饱和脂肪酸和矿物质等含量高,必需氨基酸种类较齐全,并可提取几丁质、凝集素和抗菌肽等生物活性物质,是一种优质的昆虫蛋白质饲料。研究表明,蝇蛆及其制品能够部分替代饲粮中常规蛋白质饲料,提高畜禽生长或生产性能、提升产品品质、增强机体抗氧化和免疫功能以及调节肠道菌群结构。本文综述了蝇蛆的营养特性及其应用于畜禽生产中的最新研究成果,以期为其在养殖业中的应用及进一步研究提供参考。     

World association for the advancement of veterinary parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of anthelmintics in ruminants (bovine and ovine)

During the 8th International Conference of the World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) held in Sydney, Australia, in 1977, President S. Gaafar appointed a committee to prepare international guidelines for evaluating the efficacy of anthelmintic products. The goal was to develop uniform testing standards and registration requirements to expedite the testing and approval of effective products with a minimum of labor, money, and experimental animals without sacrificing scientific validity. Achievement of such a goal would mean that data from investigators in one country could be used in registering drugs in another country.

These guidelines, which were approved by the membership at the general meeting of the 9th International Conference of the W.A.A.V.P. on July 16, 1981 in Budapest, Hungary, are only a beginning in the development of uniform international methods for testing the efficacy of anthelmintics. We now propose that they be used by the scientific community recognizing that, at this time, these guidelines have not been officially reviewed or accepted by any government regulatory authority. Investigators are encouraged to evaluate this document critically and to recommend modifications promptly to the Committee so that they may be incorporated in these guidelines before the 10th International Conference to be held in Perth, Australia in 1983.     

Foreign animal disease outbreaks, the animal welfare implications for Canada: risks apparent from international experience

Any outbreak of an Office International des Epizooties List A disease, such as classical swine fever or foot and mouth disease, has severe consequences for animal welfare, livestock production, exports of animals and animal products, and the environment. The public concern with the animal welfare effects of methods of disease eradication that result in the destruction of large numbers of uninfected animals has initiated a reconsideration of disease eradication policy in Europe. In many recent List A disease epizootics, the financial cost of addressing animal welfare concerns in healthy animals has greatly exceeded the cost of stamping out disease in infected herds. In the event of a similar incursion in Canada, the number of animals subject to welfare slaughter will be far greater than the number of infected animals killed. Current national disease eradication plans in Canada do not address the animal welfare component of disease control methods.     

中国真丝绸商品出口的国际竞争力分析

依据国际市场占有率(MS)、贸易竞争力指数(TC)和显示性比较优势指数(RCA)等3项指标数据,对我国真丝绸商品自入世以来的国际竞争力进行实证分析。以蚕丝类为代表的原料制品和以绸缎类为代表的半制成品在国际市场上具有较强竞争优势,其MS和TC指数都比较高,但是RCA指数却呈现下降趋势;以女衬衫、披肩以及领带为代表的丝绸二次制成品在国际市场上的竞争力相对较弱。实证结果说明我国依然处于蚕丝原料输出国的地位,利润空间较小的蚕丝类和绸缎类的出口占很大比例,而利润空间比较大的部分丝绸二次制成品的国际市场占有率则相对较小。提升我国真丝绸商品出口的国际竞争力,一方面要在中西部地区建立专业化、规模化的优质蚕茧生产基地,以保障高档真丝绸制成品的原料品质;另一方面要增强丝绸二次制成品生产企业在产品研发设计、生产技术、产品营销策划等方面的能力,以及改善生产设备,创建一批国际化的高档丝绸品牌,增加高附加值丝绸产品的出口量和出口额。     

Principles of transfusion medicine in small animals.

The purpose of this review was to provide the reader with an updated overview of small animal transfusion medicine, and an approach to integrating it into private practice, based on a review of the veterinary and human literature spanning the last 3 decades. Electronic, online databases that were searched included CAB International and Medline; multiple keywords or subject headings were searched that were appropriate to each of the sections reviewed: canine and feline blood groups, blood-typing and crossmatching, donors, blood collection, storage, blood components, blood transfusion, blood component therapy, blood substitutes, and adverse reactions. The safe use of blood component therapy requires knowledge of blood groups and antibody prevalence, and knowledge of the means to minimize the risk of adverse reactions by including the use of proper donors and screening assays that facilitate detection of serological incompatibility. The 2 assays available to the practitioner are crossmatching, which is readily done in-house, and blood typing. Blood typing is available in the form of a commercial testing kit, through use of purchased reagents, or via a request to an external laboratory. The risk of potentially fatal adverse reactions is higher in cats than in dogs. The decision to transfuse and the type of product to administer depend on several factors, such as the type of anemia and the size of the animal. In conclusion, transfusion medicine has become more feasible in small animal practice, with improved access to blood products through either on-site donors, the purchase of blood bank products, external donor programs, or the availability of blood component substitutes.     

Glucagon‐related peptides and the regulation of food intake in chickens

The regulatory mechanisms underlying food intake in chickens have been a focus of research in recent decades to improve production efficiency when raising chickens. Lines of evidence have revealed that a number of brain‐gut peptides function as a neurotransmitter or peripheral satiety hormone in the regulation of food intake both in mammals and chickens. Glucagon, a 29 amino acid peptide hormone, has long been known to play important roles in maintaining glucose homeostasis in mammals and birds. However, the glucagon gene encodes various peptides that are produced by tissue‐specific proglucagon processing: glucagon is produced in the pancreas, whereas oxyntomodulin (OXM), glucagon‐like peptide (GLP)‐1 and GLP‐2 are produced in the intestine and brain. Better understanding of the roles of these peptides in the regulation of energy homeostasis has led to various physiological roles being proposed in mammals. For example, GLP‐1 functions as an anorexigenic neurotransmitter in the brain and as a postprandial satiety hormone in the peripheral circulation. There is evidence that OXM and GLP‐2 also induce anorexia in mammals. Therefore, it is possible that the brain‐gut peptides OXM, GLP‐1 and GLP‐2 play physiological roles in the regulation of food intake in chickens. More recently, a novel GLP and its specific receptor were identified in the chicken brain. This review summarizes current knowledge about the role of glucagon‐related peptides in the regulation of food intake in chickens.     

抗生素替代品在养猪生产中的应用研究进展

动物长期使用抗生素可导致免疫力下降,引起畜禽内源性感染和二重感染,因此,开发绿色、高效、安全的新型饲用抗生素替代品成为当前饲料工业发展的热点。抗生素替代品种类较多,包括酸化剂、抗菌肽、中草药、微生态制剂等产品,具有安全、环保和效果显著等特点。重点对酸化剂、γ-氨基丁酸、水解单宁酸、植物提取物、抗菌肽、酶制剂、益生菌、中草药等在养猪生产中的应用进行综述,为抗生素替代品的研发提供参考。     

Epitope mapping of Campylobacter jejuni flagellar capping protein (FliD) by chicken (Gallus gallus domesticus) sera

Campylobacter jejuni, a Gram-negative rod, is a zoonotic pathogen associated with human acute bacterial gastroenteritis worldwide. The flagellum, composed of more than 35 proteins, is responsible for colonization of C. jejuni in the host gastrointestinal tract as well as inducing protective antibodies against the homologous serotype. In our previous study, we demonstrated that the flagellar capping protein (FliD) is an immunodominant protein that reacted strongly to sera from field chickens. In this communication, we mapped linear immunoreactive epitopes on FliD using a set of 158 synthetic peptides of 15-mer overlapping with 11 amino acid residues on peptide microarrays with sera from field chickens. The results from peptide microarrays showed (1) no cross-reactivity of the immobilized peptides with the secondary anti-chicken antibody in the control incubation, and (2) heterogeneous patterns of sera reacting to the immobilized peptides. The peptides that reacted to more than three chicken sera and had higher averages of fluorescence units were selected for further validation by the peptide ELISA. The results showed peptides 24, 91 and 92 had relatively high reactivity and less variation among 64 individual serum samples, indicating these peptides represented the shared immunodominant epitopes on the C. jejuni FliD protein. These peptides were also recognized by sera from chickens immunized with the purified recombinant FliD protein. The findings of the specific shared linear immunodominant epitopes on FliD in this study provide a rationale for further evaluation to determine their utility as epitope vaccines covering multiple serotypes for chicken immunization, and subsequently, for providing safer poultry products for human consumption.