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101.
102.
蜜蜂肠道菌群的调节作用及影响因素 总被引:1,自引:0,他引:1
近年来, 蜜蜂数量的大量减少导致全球养蜂业面临重要的经济损失,并对农业各个方面造成了严重后果。最新的研究表明肠道菌群与宿主的健康息息相关。综述了肠道菌群的种类和特性,阐述了肠道菌群在蜜蜂等昆虫健康中的调节作用及影响肠道菌群的因素,并对今后的研究方向进行了展望。 相似文献
103.
Fucoidans are cell wall polysaccharides found in various species of brown seaweeds. They are fucose-containing sulfated polysaccharides (FCSPs) and comprise 5–20% of the algal dry weight. Fucoidans possess multiple bioactivities, including antioxidant, anticoagulant, antithrombotic, anti-inflammatory, antiviral, anti-lipidemic, anti-metastatic, anti-diabetic and anti-cancer effects. Dietary fucoidans provide small but constant amounts of FCSPs to the intestinal tract, which can reorganize the composition of commensal microbiota altered by FCSPs, and consequently control inflammation symptoms in the intestine. Although the bioactivities of fucoidans have been well described, there is limited evidence to implicate their effect on gut microbiota and bowel health. In this review, we summarize the recent studies that introduce the fundamental characteristics of various kinds of fucoidans and discuss their potential in altering commensal microorganisms and influencing intestinal diseases. 相似文献
104.
哺乳期灌服亚精胺或精胺对早期断奶大鼠生长及肠道发育的影响 总被引:1,自引:0,他引:1
为考察断奶前多胺诱导的肠道成熟是否具有缓解早期断奶应激的作用,本研究选取同窝14d清洁级SD哺乳大鼠分别经胃管连续3d灌服5μmol亚精胺,5μmol精胺或生理盐水(对照组)。17d实施早期断奶,一半幼鼠断奶后立即致死,剩余一半独立饲养至20d后致死,测定幼鼠体重及肠道发育指标。结果表明:亚精胺和精胺促进了17d哺乳大鼠肠道成熟,表现为肠道重量、肠长、小肠蛋白质、蔗糖酶活性的升高。亚精胺和精胺可有效阻止早期断奶失重,并降低或消除了早期断奶肠道的应激反应,表现为肠道重量、肠长、肠道蛋白质、肠道DNA和蔗糖酶、乳糖酶活性在断奶前后不受影响。亚精胺和精胺对肠道杯状细胞类型有显著影响,断奶后酸性杯状细胞分别增加20.1%(P>0.05)和89.5%(P<0.05)。综上可得出,断奶前灌服亚精胺或精胺具有促进哺乳期肠道成熟,降低早期断奶应激和增强黏液屏障的作用。 相似文献
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108.
壳寡糖对吉富罗非鱼幼鱼生长性能、前肠组织结构及肠道主要菌群的影响 总被引:2,自引:2,他引:0
选用初始体质量(3.02±0.16) g的吉富罗非鱼幼鱼(Oreochromis niloticus)450尾,随机分为5组,每组3个重复,每重复30尾实验鱼,分别饲喂添加壳寡糖质量分数为0.00%(对照组)、0.10%、0.30%、0.50%和0.70%的饲料8周,考查壳寡糖对吉富罗非鱼幼鱼生长性能、前肠组织结构及肠道主要菌群的影响.结果表明,在生长性能方面,添加0.30%、0.50%和0.70%壳寡糖组增重率分别较对照组显著提高12.53%、16.17%和9.47%(P<0.05);添加壳寡糖各组较对照组饲料系数显著降低,饲料干物质和蛋白质的表观消化率均显著升高(P<0.05).在肠道组织结构方面,与对照组相比,添加0.30%和0.50%壳寡糖组的幼鱼前肠绒毛长度显著增加了18.02%和23.21%,宽度显著增加了45.21%和54.06%,密度显著增加了15.18%和19.37%(P<0.05);添加0.30%、0.50%和0.70%壳寡糖组的幼鱼肠壁厚度较对照组分别减少了16.41%、19.96%和15.00%(P<0.05).在肠道主要菌群方面,各壳寡糖添加组大肠杆菌数量均显著降低,乳酸杆菌数量显著增加(P<0.05).上述结果表明,吉富罗非鱼幼鱼饲料中添加壳寡糖可提高其生长性能,并改善肠道内环境,推荐适宜添加量为0.30%~0.50%. 相似文献
109.
S. He Z. Wu Y. Liu N. Wu Y. Tao L. Xu Z. Zhou B. Yao E. Ring 《Aquaculture Nutrition》2013,19(5):765-772
Dried distiller's grain (DDG) is considered as an alternative ingredient of dietary feed due to its high contents of protein, fibre and fat. In this study, 60 g kg‐1 of DDG was used to feed grass carp (Ctenopharyngodon idella), bluntnose black bream (Megalobrama amblycephala), gibel carp (Carassius gibelio) and black carp (Mylopharyngodon piceus) for 8 weeks, and its effect on fish production and gut allochthonous microbiota was investigated for the development of a suitable fish feed high in nutrients and low in cost for polyculture freshwater fish. DDG supplementation resulted in the less weight gain and higher feed conversion ratio of black carp (P < 0.05), but had no significant effects on other fish or parameters. PCR–denaturing gradient gel electrophoresis (DGGE) analysis indicated that all four fish species had some common and unique bacteria in their digestive tracts, and the gut microbiota of bluntnose black and gibel carp fed the control diet and DDG diets were very similar (Cs > 91%); of them, the total counts of intestinal bacteria studied by qPCR increased in grass carp (P < 0.05) and depressed in black carp (P < 0.05) when fed dietary DDG. Thus, we assumed that dietary DDG modulated production and gut microbiota of fish in a host‐specific way. 相似文献
110.
Zhigang Zhou Ørjan Karlsen Suxu He Rolf Erik Olsen Bin Yao Einar Ringø 《Aquaculture Research》2013,44(12):1889-1900
In the present study the impact on autochthonous (adherent) bacteria in proximal intestine (PI) and distal intestine (DI) of Atlantic cod ( Gadus morhua L.) was evaluated following feeding of a control diet and a diet supplemented with 5% chitin. The autochthonous gut bacteria were investigated using denaturing gradient gel electrophoresis (DGGE). Analysis of the microbiota associated with PI and DI of Atlantic cod indicate that dietary chitin modulate the intestinal bacterial community. For example, band 25 ( Escherichia coli–like), band 14 ( Anaerorhabdus furcosa–like) and band 29 (uncultured bacterium–like) in PI were depressed by dietary chitin (P < 0.05). The number of bands (23.7 ± 5.4) in DI of fish fed chitin was marginally higher than the control fish (16.7 ± 2.1) (P = 0.065), and the relative abundances of band 6 (swine faecal bacterium–like) were marginally stimulated by dietary chitin (P = 0.095). Furthermore, the present study reports several novel sequences not previously reported in the gastrointestinal tract of Atlantic cod. Whether the dietary effect of chitin on gut bacterial community has any positive effect of fish health merits further investigations. 相似文献