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101.
Biofilms of Candida spp. from the ocular conjunctiva of horses with reduced azole susceptibility: a complicating factor for the treatment of keratomycosis? 下载免费PDF全文
Raimunda Sâmia Nogueira Brilhante Paula Vago Bittencourt Débora de Souza Collares Castelo‐Branco Glaucia Morgana de Melo Guedes Jonathas Sales de Oliveira Lucas Pereira Alencar Rossana de Aguiar Cordeiro Mariana Pinheiro Evilázio Fernandes Nogueira‐Filho Waldemiro de Aquino Pereira‐Neto José Júlio Costa Sidrim Marcos Fábio Gadelha Rocha 《Veterinary ophthalmology》2017,20(6):539-546
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早期断奶是现代养猪生产中的瓶颈问题。早期断奶易造成仔猪早期断奶综合征,仔猪断奶后会出现采食量下降、生长阻滞和腹泻等一系列症状。引起这些症状的主要原因之一是断奶应激引起的仔猪肠道屏障受损。鉴于肠道微生态区系为肠道第一道防御屏障,因此,研究仔猪肠道微生态区系及其营养调控技术,对于防制仔猪早期断奶综合征、促进仔猪肠道健康、提高生产性能具有重要意义。文章针对断奶仔猪肠道微生物菌群变化及几种常用饲料添加剂(微生态制剂、植物多糖、酸化剂、微量元素、中草药及植物提取物)对肠道微生态区系调控的研究进展进行了综述。 相似文献
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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
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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
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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
107.
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
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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