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101.
Effects of dietary supplementation of a commercial prebiotic Previda® on survival,growth, immune responses and gut microbiota of Pacific white shrimp,Litopenaeus vannamei 下载免费PDF全文
J.D. Anuta A. Buentello S. Patnaik M.E. Hume A. Mustafa D.M. Gatlin III A.L. Lawrence 《Aquaculture Nutrition》2016,22(2):410-418
A 35‐day feeding trial was conducted to evaluate growth, bacterial populations of the gastrointestinal tract (GIT) and immune responses of Litopenaeus vannamei fed diets containing the commercial prebiotic Previda®. Diets were formulated to contain Previda® at 0, 0.2, 0.5, 1.0 or 1.6 g kg?1 by weight. At the end of the study, differences in weight gain and survival among treatments were not significant (P > 0.05), but denaturing gradient gel electrophoresis analysis revealed that the microbial communities in the GIT changed significantly with the inclusion of dietary Previda® at different levels. Previda® was therefore able to selectively modify the microbial communities in the shrimp's GIT. Although individual bacterial species were not identified, enteric populations in shrimp fed the prebiotic at similar levels of inclusion were genetically similar. In addition, shrimp fed Previda® at 1.6 g kg?1 responded significantly (P < 0.05) better immunologically with respect to hemocyte phagocytic capacity, haemolymph protein, hyaline cell counts and haemolymph glucose compared with shrimp fed the basal diet. Although shrimp were not exposed to virulent pathogens in this study, the observed upregulation of some of imm‐une responses upon prebiotic supplementation indicates that an improved outcome of such challenges may be anticipated in Previda®‐fed shrimp under commercial conditions. 相似文献
102.
利用宏基因组学方法,以人肠道微生物样品为原材料,构建了1个约30 000个克隆的fosmid文库.以三丁酸甘油酯为底物,通过功能筛选,获得1个酯解酶阳性克隆.对该阳性克隆构建亚克隆,挑选具有酯解酶活性的阳性亚克隆进行测序分析,最终获得1个肠道微生物来源的酯解酶基因(GenBank登录号:JQ972699).结果表明,文库克隆的平均插入片段约为40 kb,没有重复插入片段克隆.获得的酯解酶基因推演蛋白与Pyramidobacter piscolens W5455的patatin样磷脂酶同源性最高,氨基酸一致性为95%.生物信息学分析结果表明该基因可能通过Vd型分泌方式进行分泌并发挥功能.本研究是通过构建人肠道微生物宏基因组大片段文库并结合重组子功能筛选获得酯解酶的首次报道,可为食品工业提供新的酯解酶来源和筛选方法. 相似文献
103.
选择神木县畜牧科技示范园种羊场1.5~3岁健康、中等以上膘情的四种繁殖母羊共600只,将其纯种萨福克羊和萨寒、陶细、德细二元杂交肉羊随机分为3个试验组和1个对照组。试验Ⅰ、Ⅱ、Ⅲ组分别用PG、阴道栓+FSH和阴道栓+PMSG处理,处理后96 h观察结果表明:Ⅰ组的四种羊同期发情率为:萨福克羊58.3%、德细52.9%、萨寒63.3%、陶细57.5%;Ⅱ组相应为:71.9%、78.1%、83.3%、82.1%;Ⅲ组相应为:85.7%、81.8%、87.1%、81.6%。试验Ⅱ、Ⅲ组处理的母羊发情率均显著高于试验Ⅰ组(P〈0.05),Ⅱ组和Ⅲ组之间母羊发情率差异不显著(P〉0.05),试验组综合效果均极显著优于对照组。四种羊以萨寒羊同期发情率最高。三种处理的母羊受胎率差异均不显著(P〉0.05)。 相似文献
104.
Yuqin Wu Xiaonan Yin Youli Wang Tahir Mahmood Muhammad Shahid Dafei Yin Jianmin Yuan 《Animal Science Journal》2020,91(1)
This study was aimed to explore the comparative acidifying properties of 2‐hydroxy‐4‐(methylthio) butanoic acid (HMTBA) and a combination of DL‐methionine (DLM) and acidifier in male broiler production. A total of 480 1‐day‐old broiler chicks were randomly divided into four treatments: A (low HMTBA, 0.057% HMTBA); B (low acidifier, 0.05% DLM + 0.057% acidifier); C (high HMTBA, 0.284% HMTBA); and D (high acidifier, 0.25% DLM + 0.284% acidifier). At 21 d, growth performance, chyme pH, digestive enzyme activities, and intestinal microflora were measured. The pH of crop, gizzard, and ileum contents was higher in the HMTBA treatment group than in DLM + acidifier treatment group. Furthermore, acidifier supplementation promoted growth of butyrate‐producing bacteria such as Faecalibacterium, whereas high HMTBA (0.284%) inhibited the proliferation of acid‐producing bacteria including Roseburia and Collinsella. The chymotrypsin activity was lower in the HMTBA group than in the DLM + acidifier group. In contrast, high‐level HMTBA group showed higher average daily gain and average daily feed intake than the DLM + acidifier group. These results suggested that HMTBA work through different pathways with DLM plus acidifier. 相似文献
105.
Ju Kyoung Oh Jong Pyo Chae Edward Alain B. Pajarillo Sung Hun Kim Min‐Jin Kwak Jong‐Su Eun Seok Woo Chee Kwang‐Youn Whang Sae‐Hun Kim Dae‐Kyung Kang 《Animal Science Journal》2020,91(1)
Gastrointestinal microbiota impact host's biological activities, including digestion of indigestible feed components, energy harvest, and immunity. In this study, fecal microbiota of high body weight (HW) and low body weight (LW) growing pigs at 103 days of age were compared. Principal coordinates analysis separated the HW and LW groups into two clusters, indicating their potential differences between microbial community composition. Although the abundances of two major phyla, Firmicutes and Bacteroidetes, did not significantly differ between the HW and LW groups, some genera showed significant differences. Among them, Peptococcus and Eubacterium exhibited strong positive correlations with body weight (BW) and average daily gain (ADG) (Rho > 0.40), whereas Treponema, Desulfovibrio, Parabacteroides, and Ruminococcaceae_unclassified exhibited strong negative correlations with BW and ADG (Rho < ?0.40). Based on these results, the structure of intestinal microbiota may affect growth traits in pigs through host–microbe interactions. Further in‐depth studies will provide insights into how best to reshape host–microbe interactions in pigs and other animals as well. 相似文献
106.
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108.
Polyphenols are a class of non-essential phytonutrients, which are abundant in fruits and vegetables. Dietary polyphenols or foods rich in polyphenols are widely recommended for metabolic health. Indeed, polyphenols (i.e., catechins, resveratrol, and curcumin) are increasingly recognized as a regulator of lipid metabolism in host. The mechanisms, at least in part, may be highly associated with gut microbiome. This review mainly discussed the beneficial effects of dietary polyphenols on lipid metabolism. The potential mechanisms of gut microbiome are focused on the effect of dietary polyphenols on gut microbiota compositions and how gut microbiota affect polyphenol metabolism. Together, dietary polyphenols may be a useful nutritional strategy for manipulation of lipid metabolism or obesity care. 相似文献
109.
Rachel Pilla Frederic P. Gaschen James W. Barr Erin Olson Julia Honneffer Blake C. Guard Amanda B. Blake Dean Villanueva Mohammad R. Khattab Mustafa K. AlShawaqfeh Jonathan A. Lidbury Jörg M. Steiner Jan S. Suchodolski 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(5):1853-1866
110.
不同粪菌悬液处理方式对猪粪菌移植过程中细菌活性及活菌组成的影响 总被引:1,自引:0,他引:1
旨在探究不同粪菌液处理方法对其菌群活性及存活菌群物种组成的影响,为猪粪菌移植(FMT)的优化应用提供参考。本研究共设置7个试验组制备粪菌液:静置制备新鲜粪菌液组(FS)、静置制备粪菌液于-80℃冷冻1周组(FFS)、离心制备新鲜粪菌液组(FC)、离心制备粪菌液于-80℃冷冻1周组(FFC)、液氮冷冻粪便24 h静置制备粪菌液组(NS)、甘油+液氮冷冻粪便24 h静置制备粪菌液组(GNS)和液氮冷冻粪便24 h静置制备粪菌液于-80℃冷冻1周组(NFS),在37℃厌氧培养箱中平板培养48 h后,进行菌落计数。从FS、FFS、FC和FFC 4组中根据菌落形态随机挑取87个单菌落纯化后进行16S rRNA基因全长测序。结果表明,静置和离心两种方法制备新鲜粪菌液时,粪菌活性存在显著差异,离心组显著低于静置组(P<0.05)。但冷冻粪便使用静置和离心两种方法制备的菌悬液,其粪菌活性无显著差异(P>0.05)。无论是静置还是离心方法制备粪菌液,新鲜和冷冻两种不同处理方式下的粪菌活性均无显著差异(P>0.05),且对活菌的组成也无显著影响。使用静置法制备粪菌液时,FS、NS、GNS和NFS组间粪菌活性无显著差异(P>0.05)。综上表明,静置方法制备粪菌液时,超低温冷冻保存对粪菌活性及其活菌组成均无显著影响,这为大样本、长距离猪粪菌移植技术的应用提供了重要试验参考。 相似文献