兔胃肠道内微生物区系的特点及疫疾的调控

兔的胃肠道微生物区系和纤维素的消化密切相关,微生物结构正常是维持盲肠生理功能的基础。当盲肠正常菌群结构被破坏后,会导致整个消化道发生一系列病理反应,影响消化吸收功能,甚至出现全身性病理反应。家兔的胃肠道内微生物区系随年龄的增加变化很大,因此对不同日龄家兔进行饲养管理时,应采取不同措施。     

柠檬酸对肉仔鸡肠道pH值及肠道微生物的影响

长期以来的大量研究证实，胃肠道微生物大多都是有益的并与动物存在着共生关系，这种共生关系表现在畜禽消化道为微生物提供适宜生长的环境，反过来微生物提供了动物所需要的某些营养物质。尽管对消化道微生物作用的认识还不全面，但已取得一些共识：消化道微生物参与机体物质代谢、营养转化和合成，影响营养物质的分解吸收（康白，１９８８）。同时饲料是影响消化道微生物区系建立的主要环境因素之一。本试验拟通过对肉仔鸡十二指肠、盲肠３种正常菌群的观察来研究柠檬酸对肠道正常微生物的影响。１材料与方法１．１试验设计和日粮试验采用…     

兔饲料使用说明和存在的问题

<正>1家兔消化生理和对饲料需求特点1.1粗饲料不可替代家兔属于单胃草食家兔,粗纤维是其最重要的营养素之一,而且是不可替代的营养。家兔发达的盲肠内含有复杂的微生物区系,其作用如同牛羊的瘤胃。粗纤维不仅仅提供一些营养,更重要的是对于维持家兔肠道正常的微生物区系的平衡发挥重     

畜禽消化道健康定量评估五环标准之——稳定的微生物区系

胃肠道微生物不仅参与营养物质的消化吸收,还对宿主代谢和免疫调控起到重要作用。了解畜禽肠道微生物的组成结构与功能,对动物健康养殖和畜牧业发展意义重大。基于此,文章就畜禽消化道稳定的微生物区系及其影响因素进行综述,着重论述了畜禽消化道的区室化特点及其构成,并通过定义非健康的肠道微生物区系及其影响因素,定义了畜禽健康稳定的微生物区系特点及其发展规律。文章以肉鸡为例,运用Meta分析方法评估消化道关键微生物与胃肠道形态结构、宿主饲料利用效率和免疫反应的相关性,在此基础上论述了肠道微生物参与宿主消化吸收代谢、免疫及肠道完整性调控的潜在机制,为保障机体消化道健康和提高动物生产性能提供了理论依据。     

仔猪消化道微生物区系变化影响因素研究

本文简述仔猪消化道微生物区系的组成及结构，重点分析影响消化道微生物区系变化的各种因素，表明正常的微生物区系的建立对维持仔猪健康生长具有重要作用。     

调控家兔消化道生态 改善消化系统健康

兔消化道生态系统的特异性和功能多样性高度变化。消化道生态系统的生理特征包括:营养物质水解和发酵、免疫系统调节、血管形成、肠道发育和抵抗疾病的屏障作用。了解消化道生态系统并调控其功能和特异性是增强幼兔消化障碍抵抗力和饲养效率的新策略。本文综述了消化道主要发酵部位的微生物区系组成、消化道微生物区系多样性;阐述了消化道微生物区系的主要功能,以及控制兔盲肠微生物区系的方法和最佳时机。     

牛消化道正常菌群的研究

动物胃肠道内栖居有许多种微生物,它们作为一个整体彼此相互依赖,相互制约。其中大部分与胃肠道细胞接触,交换营养物质、能量或遗传信息。目前,国内外对鸡、猪、兔等单胃动物的消化道正常菌群作了大量分析和研究,并研制开发出多种微生态制剂,增进了动物健康;提高了生产力。对反刍动物消化道正常菌群,国外有微生态制剂应用于牛的试验研究,但国内这方面的研究及应用尚未见报道。本文就国内外牛消化道正常菌群的研究作一简要综述。1牛消化道正常菌群概况1.1牛瘤胃正常菌群牛瘤胃中存在着极其复杂的微生物区系,主要有原生虫和细菌两大…     

加酶益生素添加时间对哺乳断奶仔猪日增重和腹泻率的影响

在自然条件下,随着外界微生物进入胃肠道,不同种属的微生物经过生物演化最终形成相对稳定的胃肠道微生物区系,微生物区系一旦建立,将终生维持和稳定.在仔猪微生物区系建立前,以先人为主策略接种有益微生物,有助于建立正常的微生物区系,排除或控制潜在的病原体.     

鸡盲肠微生物微生态调控研究进展

1引 言 　　鸡与哺乳动物相比，消化道短，成年鸡的消化道长 150 cm左右，大肠仅有 3～ 4 cm长。但家禽有成对的盲肠，鸡的盲肠长 3～ 5 cm。盲肠是鸡消化道微生物活动最大的器官。虽然目前对鸡盲肠微生物微生态学的研究远没有反刍动物瘤胃和猪后肠微生物微生态学的研究深入，但在利用健康鸡盲肠细菌培养物的竞争排斥作用来控制有害菌如沙门氏菌，以及通过饲料中添加营养物来调控盲肠微生物菌群方面已取得了可喜的成果。 　　在肠道内定居的具有保护作用的有益微生物菌群是比较稳定的。肠道固有的微生物区系的最重要的作用是阻止入侵的病原…     

饲粮不同比例生姜秸秆替代花生秧对莱芜黑兔胃肠道发育、盲肠发酵和盲肠微生物区系的影响

本试验旨在研究饲粮不同比例生姜秸秆替代花生秧对莱芜黑兔胃肠道发育、小肠组织形态结构、盲肠发酵和盲肠内容物微生物区系的影响。试验选取45日龄育肥期莱芜黑兔160只,随机分为4组,分别饲喂以生姜秸秆替代0(A组)、5%(B组)、10%(C组)和15%(D组)花生秧的全价配合饲料,每组5个重复,每个重复8只家兔。预试期7 d,正试期47 d。结果表明:1)饲粮不同比例生姜秸秆替代花生秧对莱芜黑兔胃相对重量、胃内容物相对重量和大肠内容物相对重量有显著影响(P 0.05),其中C组和D组的胃相对重量显著高于A组和B组(P 0.05),D组胃内容物相对重量显著高于其他各组(P0.05),B组、C组和D组大肠内容物相对重量显著高于A组(P0.05)。2)饲粮不同比例生姜秸秆替代花生秧对莱芜黑兔小肠肌层厚度有显著影响(P0.05),D组显著高于其他各组(P0.05)。3)饲粮不同比例生姜秸秆替代花生秧对莱芜黑兔盲肠内容物中乙酸、丙酸和丁酸含量以及乙酸/(丙酸+丁酸)有显著影响(P 0.05),其中D组乙酸含量以及乙酸/(丙酸+丁酸)显著高于其他各组(P0.05),丙酸和丁酸含量显著低于A组和B组(P0.05)。4)莱芜黑兔盲肠内容物微生物组成在门水平上占据主导地位的主要有厚壁菌门(Firmicutes)、拟杆菌门(Bacteroidetes)、软壁菌门(Tenericutes),Shannon指数在D组与A组之间存在显著差异(P0.05),表明高比例生姜秸秆替代花生秧能够影响盲肠内容物微生物区系。综上所述,饲粮适宜比例(5%～10%)的生姜秸秆替代花生秧对莱芜黑兔的胃肠道发育、小肠组织形态结构、盲肠发酵和盲肠内容物微生物区系无明显不良影响,生姜秸秆可用作家兔粗饲料原料在生产上使用。     

Resistance to antibiotics in the normal flora of animals.

The normal bacterial flora contains antibiotic resistance genes to various degrees, even in individuals with no history of exposure to commercially prepared antibiotics. Several factors seem to increase the number of antibiotic-resistant bacteria in feces. One important factor is the exposure of the intestinal flora to antibacterial drugs. Antibiotics used as feed additives seem to play an important role in the development of antibiotic resistance in normal flora bacteria. The use of avoparcin as a feed additive has demonstrated that an antibiotic considered "safe" is responsible for increased levels of antibiotic resistance in the normal flora enterococci of animals fed with avoparcin and possibly in humans consuming products from these animals. However, other factors like stress from temperature, crowding, and management also seem to contribute to the occurrence of antibiotic resistance in normal flora bacteria. The normal flora of animals has been studied with respect to the development of antibiotic resistance over four decades, but there are few studies with the intestinal flora as the main focus. The results of earlier studies are valuable when focused against the recent understanding of mobile genetics responsible for bacterial antibiotic resistance. New studies should be undertaken to assess whether the development of antibiotic resistance in the normal flora is directly linked to the dramatic increase in antibiotic resistance of bacterial pathogens. Bacteria of the normal flora, often disregarded scientifically, should be studied with the intention of using them as active protection against infectious diseases and thereby contributing to the overall reduction of use of antibioties in both animals and humans.     

Microbiology of the canine and feline eye

Knowledge of the microbiology of the canine and feline eye in normal and pathologic states is an important aspect of the clinician's assessment of external ocular disease. Gram-positive bacteria predominate in surveys of microbial flora in normal and diseased eyes. These same organisms are routinely isolated from skin and the upper respiratory tract. Injury to the eye may result in proliferation and potential pathogenicity of normal ocular flora. A variety of bacterial, fungal, viral, and other microbial isolates affect the diagnosis and treatment of external ocular disease.     

The bacterial flora of the normal canine vagina compared with that of vaginal exudates

The aerobic bacterial flora (excluding Mycoplasma spp.) of the vagina of sixty-two clinically normal bitches was determined and the species most frequently isolated, in decreasing order, were: Escherichia colt , Streptococcus 'viridans', Staphylococcus aureus and Streptococcus cards .
From the vaginal exudates of seventy-two bitches with vaginitis, the order of frequency was: E. coli , Strep, canis and Staph. aureus .
The only consistent difference between the bacterial flora from the two sources was the relatively higher numbers of bacteria in the vaginal exudates.     

Concentration of airborne endotoxins and airborne bacteria in Chinese rabbit houses

Concentration of airborne endotoxins, airborne aerobic bacteria and airborne aerobic gram-negative bacteria were measured in 3 rabbit houses. Further, the species composition of the airborne gram-negative bacterial flora was investigated. The total amount of airborne endotoxin ranged from 22 to 774 EU/m3 (Endotoxin Units/m3). The number of total airborne aerobic bacteria varied between 780 and 20100 CFU/m3, the number of airborne aerobic gram-negative bacteria between 39 and 1030 CFU/m3. Most gram-negative bacterial isolates belonged to the family Enterobacteriaceae with E. coli as primary species. In two rabbit houses also airborne Pasteurella multocida spp. multocida, the most common respiratory pathogen of rabbits, was isolated.     

Significance of the vaginal bacterial flora in the bitch: a review.

The literature on the bacterial flora in the vagina of the bitch is reviewed. The bacterial flora in the vagina of healthy bitches is compared with the flora of infertile bitches and bitches with vaginitis, and the role of Brucella canis as a cause of infertility is evaluated. Several investigators have recommended that bitches with reproductive disorders be treated with antibacterial drugs, but there is very little knowledge of the effect of this therapy on the bacterial flora in the vagina.     

Effects of hormonal therapy on the microbiology of seborrheic dogs.

Quantitative and qualitative bacterial assays were performed on the skin of three dogs with endocrine-related primary metabolic seborrhea. After the dogs were treated (thyroid supplementation or castration, bacterial analyses were again performed on the same sites. Before therapy, the dogs had a cutaneous flora composed mainly of Staphylococcus aureus coagulase-positive organisms. After therapy, there was a significantly lower bacterial count, and two of the dogs had floras consisting mainly of coagulase-negative cocci. During the study, the two dogs that reverted bacteriologically to a normal cutaneous microenvironment became normal dermatologically. The third dog improved, but continued to have minor signs of seborrhea.     

Ribosomal RNA-based analysis of the bacterial flora from the conjunctivae of cattle with bovine keratoconjunctivitis (BKC)

Bovine keratoconjunctivitis (BKC), colloquially referred to as 'pinkeye', is a disease affecting cattle worldwide; it costs cattle producers millions of dollars in economic loss annually. While Moraxella spp. are the primary etiologic agent of pinkeye, surveys of flora from the conjunctivae of livestock from around the world have indicated that a variety of bacterial commensals occupy this niche. We used molecular biology-based methods to determine the composition of bacterial flora in the conjunctivae of normal dairy and beef cattle from Maryland (n=113), and beef cattle with clinical BKC from Louisiana (n=42). Three regimens were used: 16S rRNA PCR and DGGE analysis of amplicons; 16S rRNA PCR and cloning of amplicons into Escherichia coli followed by screening and sequencing of clones harboring inserts; and culture of bacteria on chromogenic agar followed by 16S rRNA PCR and sequencing. Most taxa were comprised of saprophytes found in the environment, such as Bacillus, Pantoea, E. coli, and Exiguobacterium. Moraxella spp. were infrequently observed. Some species, such as Propionibacterium acnes, represent taxa not previously associated with the conjunctivae. Bacillus pumilus and Bacillus licheniformis isolates from the conjunctivae of Maryland cattle were genetically distinct from isolates previously implicated in septic infections in cattle at the same location. We conclude that employing 16S rRNA-based methods for bacterial identification can be useful in defining the flora present in the conjunctivae of normal cattle, and those with BKC.     

A Preliminary Study on the Intestinal Flora of Cecum and Colon of Eight, Ten and 12 Week Old Swine

Using a replica-plating method and differential culture media, members of the Enterobacteriaceae and Pseudomonaceae were determined quantitatively in the colon and cecum content of pigs from different litters, born on the same farm and kept under the same environmental conditions, from the age of six weeks. The bacterial flora in pigs of eight, ten and 12 weeks of age showed little significant quantitative variation. Pigs of 12 weeks of age differed significantly from younger ones with respect to Aeromonas, Edwardsiella, staphylococci and molds. The existence of a variable flora is underlined as well as the fact that Vibrio coli represents an important member of the intestinal flora at that age. No significant variation in the pH of the chyme of the colon and cecum was recorded.     

Intestinal flora studies in rabbit mucoid enteritis.

The clinical and bacteriological examination of spontaneous and experimental cases of mucoid enteritis on a large rabbit farm indicated that the mucin accumulations in the colon are a consequence of constipation. This opinion is supported by the results obtained following ligation of the proximal colon. These findings suggest that rabbit mucoid enteritis is not a specific disease entity but a general response to the factors which cause constipation. Studies of the bacterial flora of the gut in spontaneous and experimental cases suggest that while there is a notable increase in the number of coliforms and clostridia over the healthy controls, these organisms only play a secondary role.     

圈养大熊猫食性转换前期肠道细菌多样性

为了探讨大熊猫食性转换前期肠道菌群的多样性与差异性。对3只处于夏季食性转换前期大熊猫粪便细菌总DNA进行ERIC—PCR分析,并构建16SrDNA克隆文库,采用限制性内切酶HinfI、MsPI对其进行RFLP（restric—tionfragmentlengthpolymorphism）及测序分析。研究表明,食性转换前期大熊猫肠道细菌主要由硬壁菌门和变形菌门组成。其中7月份样品中以梭菌属和醋杆菌属为主;8月份以八迭球菌属和埃希氏菌属为主;9月份以链球菌属和埃希氏菌属为主。此外在3个月中均发现一定比例的未培养细菌。结果表明：随着食性转换前期的过渡,大熊猫肠道菌群发生了改变。由硬壁菌门中的梭菌属渐变到以球菌属为主,由变形菌门的醋杆菌属渐变到以肠杆菌为主。