共查询到20条相似文献,搜索用时 78 毫秒
1.
2.
在脊椎动物的肠道内,存在着数量庞大、结构多样、动态变化的微生物群,它们对肠道的生理、代谢、免疫等具有重要的作用。在自然条件下,这些微生物和真核生物(如蠕虫、原生动物、真菌等)共同存在于脊椎动物肠道内。寄生虫与微生物群均可显著改变机体肠道生理与免疫环境,为它们之间的相互作用创造了机会。肠道微生物与寄生虫之间的相互作用会极大地影响感染的结果,进而对宿主的健康产生重要影响。如寄生虫感染会影响宿主与微生物的相互作用关系,从而促使或保护宿主免受细菌的侵害。另一方面,菌群又会影响寄生虫的定植、繁殖和毒性,使其沿着与宿主寄生性-互惠共生性的生存模式发展。这些相互作用的机理与结果是微生物学与寄生虫学之间交叉研究的前沿课题。笔者对近年来有关肠道寄生虫与肠道微生物间相互作用的最新研究成果进行了总结,并对其可能未考虑到的因素提出了自己的观点,旨在为肠道寄生虫病防控及肠道菌群研究提供参考。 相似文献
3.
益生素可改善肠道微生物平衡和饲料卫生 总被引:3,自引:0,他引:3
肠道菌群与宿主动物间的关系是微妙的 ,而且二者间的应激作用对生产不利。即使在现代生产条件下 ,环境卫生改善 ,饲料配制合理 ,饲料中添加促生长剂、药物、口服疫苗 ,二者间的平衡也可能出现紊乱。随着对细菌性感染的了解 ,人们开始用饲料添加剂影响生物调节过程和通过稳定肠道菌群降低腹泻次数或消除腹泻。益生素与抗生素是有区别的 ,其微生物分类如下 :1母猪乳中细菌 :乳酸片球菌 ,嗜酸乳杆菌1 ,鼠李糖乳杆菌 ,胚芽乳杆菌 ,粪肠球菌。 2活酵母 :酿酒酵母。3产芽孢菌 :枯草芽孢杆菌 ,蜡状芽孢杆菌 ,地衣芽孢杆菌。 4其它 :米曲霉。益生素… 相似文献
4.
猪不同部位的胃肠道有不同的构造与功能,以提供消化吸收所需要的最适当条件。借着胃的排空将食糜送至小肠,食糜在小肠前段的流动速度比后段快。日粮成分、胃、小肠、胰和胆的分泌物决定胃与小肠上半部食糜的组成成分。当食糜进入肠道后段时,其流速与氧含量降低,组成成分受到消化、分泌与微生物作用而改变。小肠黏膜吸附水解后的营养成分并将其带入体内。 相似文献
5.
6.
7.
柠檬酸对肉仔鸡肠道pH值及肠道微生物的影响 总被引:10,自引:3,他引:7
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… 相似文献
8.
肠道微生物是当前研究的热点,鹅肠道微生物的组成与丰富程度不仅和鹅的生长性能密切相关,而且在鹅机体生理活动中具有一定的调节作用,同时与疾病的发生和发展具有密切的联系.通过研究鹅肠道微生物的调节,从而达到促生长或者治疗疾病的目的,是目前鹅研究探寻的新方向.文章主要综述了鹅肠道微生物的组成及其变化规律,以期为鹅产业生物饲料的... 相似文献
9.
10.
动物体肠道中存在数以亿计的微生物,这些共生的微生物能辅助动物体消化代谢和维持肠道稳态。但微生物及其代谢产物同样可以作为抗原影响肠道的正常功能。正常情况下,肠道免疫系统能准确辨识共生微生物及其代谢产物,对其做出免疫耐受,维持内环境稳态;此外,肠道免疫系统还可以避免由于对无害抗原产生反应而造成免疫资源的浪费。免疫耐受已被广泛应用于临床医学,用于减少器官移植后排斥现象的发生,降低子宫对胎儿的免疫排斥反应等。但就如何利用免疫耐受机制减缓反刍动物瘤胃酸中毒,提高瘤胃微生物蛋白质的合成和利用效率,完善益生素的饲用规程仍鲜有报道。为此,本综述就免疫耐受的一般概念和应用、肠道免疫系统的组成和功能、肠道共生微生物的免疫原性以及肠道免疫耐受的形成机制进行了阐述。 相似文献
11.
12.
赵瑜 《国外畜牧学(猪与禽)》2014,(12):6-8
猪肠道菌群由800余种细菌组成,这些细菌是其抵御病原微生物入侵的第一道屏障。肠道微生物则是以维持仔猪断奶时肠道微生物平衡和稳定为目的的日粮干预策略的一个重要指标。 相似文献
13.
《中国兽医学报》2020,(2):311-317
采用人工肌肉注射类志贺邻单胞菌(Pseudomonas shigella)后,以针对细菌16S rRNA基因高通量测序技术进行感染鲟鱼肠道菌群组成和多样性分析,结果显示:感染组鲟鱼肠道菌群多样性指数(Chaol、ACE、observed_species、 Shannon和Simpson)均显著低于对照组(P<0.05);感染组和对照组鲟鱼肠道优势菌群均为梭杆菌门(Fusobacteria)、变形菌门(Proteobacteria)、拟杆菌门(Bacteriodia)和厚壁菌门(Firmicute),但感染组鲟鱼肠道拟杆菌门细菌丰度显著小于对照组(P<0.05),而变形菌门(特别是邻单胞菌属)细菌丰度显著大于对照组(P<0.05)。结果表明,类志贺邻单胞菌感染能导致鲟鱼肠道菌群物种多样性和丰度显著变化,为鲟鱼细菌性疾病防控提供了科学依据。 相似文献
14.
Qi Wang Qian Sun Renli Qi Jing Wang Xiaoyu Qiu Zuohua Liu Jinxiu Huang 《Journal of animal physiology and animal nutrition》2019,103(6):1908-1918
This study investigated the effect of Lactobacillus plantarum strain 299v on gut health in suckling piglets. Sixty newborn piglets were assigned to control and probiotic treatments, with three litters per treatment (ten piglets/litter). From days 1 to 20 of life, piglets were orally administered a placebo of 0.1% peptone or 1.0 × 1010 CFU L. plantarum 299v daily. Six piglets per treatment were sacrificed on day 20, and intestinal tissues (including duodenum, jejunum, ileum and colon) and the intestinal contents from colon segments were collected. The results demonstrated that piglets treated with L. plantarum 299v had a lower diarrhoea incidence than the controls. L. plantarum 299v administration significantly increased the ratio of the villus height to the crypt depth in the jejunum and ileum, as well as the mRNA expression of jejunal occludin and ileal zonula occludens 1 (ZO‐1). The L. plantarum treatment also increased the mRNA abundance of porcine β‐defensin 2 (pBD2) and pBD3 in the jejunum and ileum and of toll‐like receptors (TLRs), such as TLR2, TLR4, TLR6 and TLR9 in the ileum, and significantly upregulated the mRNA abundances of ileal pBD1 and colonic TLR4. Additionally, the L. plantarum 299v treatment significantly changed the structure of the colonic microbiota, as evidenced by the obvious increases in the relative abundances of the phyla Firmicutes and Actinobacteria and of the genus Lactobacillus. Our findings indicate that L. plantarum 299v facilitates the gut health of suckling piglets, probably by improving the intestinal morphology and intestinal barrier function and by modifying the structure of the gut microbiota. 相似文献
15.
G Laycock L Sait C Inman M Lewis H Smidt P van Diemen F Jorgensen M Stevens M Bailey 《Veterinary immunology and immunopathology》2012,149(3-4):216-224
Maximising the ability of piglets to survive exposure to pathogens is essential to reduce early piglet mortality, an important factor in efficient commercial pig production. Mortality rates can be influenced by many factors, including early colonization by microbial commensals. Here we describe the development of an intestinal microbiota, the Bristol microbiota, for use in gnotobiotic pigs and its influence on synthesis of systemic immunoglobulins. Such a microbiota will be of value in studies of the consequences of early microbial colonization on development of the intestinal immune system and subsequent susceptibility to disease. Gnotobiotic pig studies lack a well-established intestinal microbiota. The use of the Altered Schaedler Flora (ASF), a murine intestinal microbiota, to colonize the intestines of Caesarean-derived, gnotobiotic pigs prior to gut closure, resulted in unreliable colonization with most (but not all) strains of the ASF. Subsequently, a novel, simpler porcine microbiota was developed. The novel microbiota reliably colonized the length of the intestinal tract when administered to gnotobiotic piglets. No health problems were observed, and the novel microbiota induced a systemic increase in serum immunoglobulins, in particular IgA and IgM. The Bristol microbiota will be of value for highly controlled, reproducible experiments of the consequences of early microbial colonization on susceptibility to disease in neonatal piglets, and as a biomedical model for the impact of microbial colonization on development of the intestinal mucosa and immune system in neonates. 相似文献
16.
The aim of this study was to investigate the prevalence of acquired antimicrobial resistance in the resident intestinal microbiota of cats and to identify significant differences between various cat populations. Escherichia coli, Enterococcus faecalis, E. faecium and Streptococcus canis were isolated as faecal indicator bacteria from rectal swabs of 47 individually owned cats, 47 cattery cats and 18 hospitalised cats, and submitted through antimicrobial sensitivity tests. The results revealed that bacteria isolated from hospitalised and/or cattery cats were more frequently resistant than those from individually owned cats. E. coli isolates from hospitalised cats were particularly resistant to ampicillin, tetracycline and sulfonamide. Both enterococci and streptococci showed high resistance to tetracycline and in somewhat lesser extent to erythromycin and tylosin. Most E. faecium isolates were resistant to lincomycin and penicillin. One E. faecalis as well as one E. faecium isolate from hospitalised cats showed 'high-level resistance' (MIC > 500 microg/ml) against gentamicin, a commonly used antimicrobial agent in case of human enterococcal infections. The results of this research demonstrate that the extent of acquired antimicrobial resistance in the intestinal microbiota of cats depends on the social environment of the investigated population. It is obvious that the flora of healthy cats may act as a reservoir of resistance genes. 相似文献
17.
葡萄糖酸对断奶仔猪生产性能、肠道微生物区系和肠黏膜形态结构的影响 总被引:1,自引:0,他引:1
葡萄糖酸(GA)是由葡萄糖在葡萄糖酸菌不完全氧化下产生的,当饲喂单胃动物时,GA很难在小肠内吸收,而主要在肠后段发酵成丁酸.本试验研究了GA对断奶仔猪生产性能、肠道微生物和肠壁组织形态的影响.仔猪日粮中添加GA,体外盲肠发酵24h后,日粮中的GA增加了总产气量和最快产气速度(线性,P<0.001).发酵4、8、24h,盲肠液中氨含量呈线性降低(二次,P<0.01).发酵24h后,随着GA的添加量,总短链脂肪酸、乙酸、丙酸、正丁酸、乙酸:丙酸、(乙酸 丁酸):丙酸呈线性增加(P<0.001).体内试验选择48头断奶仔猪,随机分成4个处理,日粮中的GA分别为0、3000、6000和12000mg/kg.试验结果表明,饲喂GA日粮与对照组相比,提高了断奶仔猪的平均日增重,GA为3000、6000mg/kg时,分别增加了13%(P=:0.11)和14%(P<0.05);日粮中添加GA对饲料转化率无影响:GA对肠道中的梭状芽胞杆菌、肠杆菌科细菌和乳酸菌菌落数无影响:日粮中添加GA,提高了空肠中总的短链脂肪酸含量(GA为3000、6000和12000mg/kg时,分别增加了174%、87%和74%);但是,GA对空肠、回肠、盲肠中肠壁组织学形态无影响.结论:断奶仔猪日粮中添加GA可以提高动物的生产性能和改善肠道微生物区系. 相似文献
18.
19.
P. Moura S. Marques L. Alves J.P.B. Freire L.F. Cunha M.P. Esteves 《Livestock Science》2007,108(1-3):244-248
The effect of xylo-oligosaccharides (XOS), a probiotic culture of Saccharomyces cerevisiae (SC) and the combined administration of XOS and SC on the piglet intestinal microbiota was investigated. Twenty four weaned piglets were fed during 4 weeks with one of the following diets: (BD) basal diet; (BD + XOS) basal diet supplemented with xylo-oligosaccharides (20 g kg− 1); (BD + SC) basal diet supplemented with S. cerevisiae (6 × 109 CFU kg− 1); and (BD + XOS + SC) basal diet supplemented with xylo-oligosaccharides and S. cerevisiae. Samples from the ileum, caecum and colon were collected and analysed for total anaerobes growing in XOS or glucose, xylose and arabinose (GXA) containing media. Specific primers were used to evaluate differences in Bifidobacterium and Lactobacillus populations and ERIC PCR to fingerprint the intestinal microbiota.
The lowest number of culturable bacteria was obtained from the ileum of animals fed BD + XOS. The highest PCR titres with Lactobacillus group-specific primers in BD and BD + SC were obtained in the caecal contents. In XOS-supplemented diets the PCR titres were increased or maintained, from the caecum to the colon. Bifidobacteria were not detected in any samples using genus-specific primers. In the dendrogram from ERIC PCR, the piglets fed with XOS diets presented the highest similarity between samples and probiotic reference strains. 相似文献
20.
Jing Liu Sydney N.Stewart Kelsy Robinson Qing Yang Wentao Lyu Melanie A.Whitmore Guolong Zhang 《畜牧与生物技术杂志(英文版)》2021,(3):1073-1088
Background: Intestinal microbiota plays a key role in nutrient digestion and utilization with a profound impact on feed efficiency of livestock animals. However, the intestinal microbes that are critically involved in feed efficiency remain elusive.Methods: To identify intestinal bacteria associated with residual feed intake(RFI) in chickens, male Cobb broiler chicks were individually housed from day 14 to day 35. Individual RFI values were calculated for 56 chickens.Luminal contents were collected from the ileum, cecum, and cloaca of each animal on day 35. Bacterial DNA was isolated and subjected to 16 S rRNA gene sequencing. Intestinal microbiota was classified to the feature level using Deblur and QIIME 2. High and low RFI groups were formed by selecting 15 and 17 chickens with the most extreme RFI values for subsequent LEfSe comparison of the difference in the microbiota. Spearman correlation analysis was further performed to identify correlations between the intestinal microbiota composition and RFI.Results: No significant difference in evenness, richness, and overall diversity of the microbiota in the ileum, cecum,or cloaca was observed between high and low RFI chickens. However, LEfSe analysis revealed a number of bacterial features being differentially enriched in either high or low RFI chickens. Spearman correlation analysis further identified many differentially enriched bacterial features to be significantly correlated with RFI(P 0.05). Importantly,not all short-chain fatty acid(SCFA) producers showed a positive association with RFI. While two novel members of Oscillibacter and Butyricicoccus were more abundant in low-RFI, high-efficiency chickens, several other SCFA producers such as Subdoligranulum variabile and two related Peptostreptococcaceae members were negatively associated with feed efficiency. Moreover, a few closely-related Lachnospiraceae family members showed a positive correlation with feed efficiency, while others of the same family displayed an opposite relationship.Conclusions: Our results highlight the complexity of the intestinal microbiota and a need to differentiate the bacteria to the species, subspecies, and even strain levels in order to reveal their true association with feed efficiency. Identification of RFI-associated bacteria provides important leads to manipulate the intestinal microbiota for improving production efficiency, profitability, and sustainability of poultry production. 相似文献