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101.
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   
102.
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   
103.
双歧杆菌具有调节肠道菌群、缓解功能性胃肠道疾病的功能,是目前广为使用的用于改善人体肠道的益生菌之一。炎症性肠病(inflammatory bowel disease,IBD)是一种慢性复发性炎症性疾病,该疾病伴随着肠黏膜溃疡、细胞死亡,并且容易复发。近年来,相关报道在肠炎治疗方面提到了双歧杆菌的益生作用。本文概述双歧杆菌、双歧杆菌产品、双歧杆菌代谢物对IBD的缓解效果,为双歧杆菌在医药方面的应用提供新的研究方向。  相似文献   
104.
功能性便秘是一种临床上比较常见的消化系统疾病,可引发一系列疾病,因此对该疾病的预防和治疗具有重要意义。双歧杆菌是肠道固有菌群之一,其对缓解功能性便秘有明显效果。本文从肠道菌群与功能性便秘的关系、双歧杆菌缓解便秘的机制以及双歧杆菌不同菌株缓解功能性便秘的效果等方面对双歧杆菌缓解功能性便秘的国内外研究进展进行综述,以期为双歧杆菌功能性菌株的深度开发及其用于缓解便秘机制的深入研究提供思路。  相似文献   
105.
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   
106.
107.
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   
108.
109.
The slash-and-burn system is a subsistence agronomical practice widespread in tropical areas worldwide. This system has been extensively studied,especially for its impacts on agronomical aspects and soil physicochemical properties; however, knowledge of soil microbial diversity under slash and bum is scarce. In this study, for the first time, soil bacterial diversity of three locations from Central Mozambique, where slash and burn has been practiced for different durations of the forest fallow p...  相似文献   
110.
Based on the respiratory quinone profile, changes in the structure of microbial communities in the soil samples from Nagoya University Farm were monitored after the treatment with 1% of a mixture of glucose and peptone. Samples of two soils differing in the fertilization history were examined: CF-soil with the application of only chemical fertilizers and FYM-soil with the application of only farmyard manure at a high rate. In the CF-soil, the amount of water-soluble organic carbon (WOC), indicator of the mixture of glucose and peptone, decreased to the original level after 14 d. After 7 d, the soil pH reached the maximum level, then decreased gradually. Changes in the inorganic nitrogen levels in the water extract also reflected the 14-d period of mineralization. The amount of respiratory quinones reached maximum levels after 7 d and gradually decreased, reflecting the changes in the microbial biomass. The quinone composition significantly changed during the 14-d period and returned to a profile similar to the original one after 28 d. Diversity of quinones significantly decreased during the 14-d period due to the predominance of ubiquinone with 9 isoprenoid units. In the FYM-soil, the amount of WOC decreased to the original level after 1 d, and the pH and inorganic nitrogen levels in the water extract reflected the one-day mineralization period, and nitrification started after 3 d. Although the amount of quinones indicated an increase in the microbial biomass for 14 d, the quinone composition did not change. These findings suggested that long-term application of farmyard manure resulted in stable microbial communities in response to the incorporation of organic matter in soil.  相似文献   
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