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91.
Background: Giardiasis is a common, potentially zoonotic disease, and dogs often harbor and shed cysts without showing clinical signs. Treatment with the probiotic Enterococcus faecium SF68 has been shown to stimulate mucosal and systemic immunity in a variety of animal models and in young dogs, and to reduce giardial cyst and antigen shedding in rodents.
Hypothesis: Adult dogs with chronic naturally acquired giardiasis will have decreased giardial fecal cyst and antigen shedding and increased innate and adaptive immunity after 6 weeks probiotic treatment with E. faecium SF68.
Animals: Twenty adult dogs.
Methods: After a 6-week dietary equilibration period, dogs were randomized to receive E. faecium SF68 or placebo for 6 weeks, and then crossed over to the alternate treatment. We measured cyst shedding, fecal giardial antigen, fecal immunoglobulin A (IgA) concentration, and circulating leukocyte phagocytic activity at multiple timepoints to determine the effect of E. faecium SF68 on giardiasis and immune responses in these dogs.
Results: No differences were observed between placebo or E. faecium SF68 treatment for giardial cyst shedding, fecal antigen shedding, fecal IgA concentration, or leukocyte phagocytic activity.
Conclusions: Short-term treatment with E. faecium SF68 of dogs with chronic naturally acquired subclinical giardiasis fails to affect giardial cyst shedding or antigen content and does not alter innate or adaptive immune responses.  相似文献   
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探讨了以植物生物反应器开发利用抗菌肽类物质防治水产动物病害的效果和机理。以携带中国明对虾抗菌肽—对虾素3-2的转基因水稻米糠制作罗非鱼饲料,研究其对饲料腐败和吉富罗非鱼嗜水气单胞菌肠炎的抑制效果。通过测定米糠和饲料中的霉菌总数、细菌总数,发现水稻中表达的对虾素3-2能有效抑制饲料中的霉菌与细菌的繁殖,对于保持饲料品质具有显著的效果。选取规格一致、体质健壮的吉富罗非鱼,随机分成5组,每组3个重复,分别投喂含20%非转基因米糠的饲料与含不同质量比(10%、20%、30%)的转基因米糠的饲料。通过嗜水气单胞菌攻毒保护实验,结果发现,转基因米糠对罗非鱼嗜水气单胞菌肠炎具有显著的保护效果。对吉富罗非鱼的肠道主要微生物数量、中肠石蜡切片的进一步分析发现,摄食转基因米糠饲料组的罗非鱼肠道内大肠杆菌比例降低,乳酸菌比例提高,肠道微绒毛的结构完整性显著改善。由此推断抗菌肽转基因水稻的防病效果可能与肠道微生物的改变和对肠道结构的保护作用有关。但是石蜡切片发现过量添加转基因米糠(30%)也会导致吉富罗非鱼肠道上皮细胞损伤。  相似文献   
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An 8‐week feeding trial was conducted to investigate the effects of dietary rapeseed meal (RM) and glutathione supplementation (400 mg kg?1) on growth and intestinal microbiota of grass carp (Ctenopharyngodon idellus). Dietary 450 g kg?1 RM decreased growth and feed intake, while increased the activities of serum alkaline phosphatase (ALP), aspartate aminotransferase (AST) and alanine transaminase (ALT). The hepatic damages were also observed the significant lower condition factor (CF), hepatosomatic index (HSI) and the symbol of parenchymal damage. Glutathione supplementation increased weight gain and feed intake while significantly decreased the three serum biochemistry parameters compared with the RM group. In addition, HSI, CF and pathology reports revealed that glutathione supplementation alleviated the damage caused by RM on the fish liver. In addition, glutathione had a positive effect on the intestinal digestive capacity. PCR‐denaturing gradient gel electrophoresis (DGGE) analysis indicated a higher similarity between dietary glutathione supplementation and control group. In conclusion, we demonstrated dietary 450 g kg?1 rapeseed meal lead to negative health outcomes, while glutathione supplementation neutralize the adverse effect of rapeseed meal presented in aqua feed through alleviating the damage factors on the fish liver.  相似文献   
95.
This study investigated the effect of supplementation of a Bacillus subtilis strain DSM 17299 on broilers, including evaluation of performance, nutrient digestibility, intestinal morphology, and content pH. The treatments also were evaluated for economic value based on performance and dietary costs. Performance was improved for probiotic treated birds for wk one through 5 post hatch, and economic evaluation at wk 6 demonstrated that the addition of the probiotic reduced production costs. Total tract digestibility of dry matter (DM), crude protein (CP), and apparent metabolizable energy were improved in probiotic supplemented broiler chickens. Addition of the probiotic increased the pH of the intestinal content. The relative weight and relative length of the duodenum decreased by probiotic supplementation. Overall, B. subtilis DSM 17299 resulted in an improvement in performance and a decrease in production costs when fed to broiler chickens. The increases in nutrient digestibility of birds fed the B. subtilis DSM 17299 correlate well with the increased performance noted over the same growing periods.  相似文献   
96.
Lysozyme is a potential replacement for antibiotics in the poultry industry. Two trials were conducted using new or used litter to determine the effect of 100 ppm lysozyme in feed on growth performance and intestinal microbiota of broiler chickens in each period of the growth cycle. The new litter trial and used litter trial were each analyzed as a one-way analysis of variance with length of time in which 100 ppm lysozyme was fed to the birds as the main factor (no lysozyme d zero to 35; positive lysozyme d zero to 4; positive lysozyme d 5 to 14; positive lysozyme d 15 to 24; positive lysozyme d 25 to 35; positive lysozyme d zero to 35; positive virginiamycin d zero to 35). Effects of lysozyme were not detected under clean conditions (P > 0.05). When used litter was provided, growth performance was not improved by lysozyme (P > 0.05). However, feeding lysozyme to birds from d 5 to 14 and throughout the trial reduced the number of E. coli in the ileum compared with feeding virginiamycin (positive lysozyme d 5 to 14 and zero to 35, and virginiamycin d zero to 35: 1.7 × 104 cfu g−1, 1.9 × 104 cfu g−1 and 9.3 × 104 cfu g−1, respectively) to birds (P < 0.05). Dietary lysozyme at 100 ppm can change intestinal microbiota of broiler chickens.  相似文献   
97.
本试验旨在比较肥胖型的金华猪和瘦肉型的长白猪肠道古菌结构的差异,分析菌群移植小鼠肠道古菌结构。采集金华猪和长白猪的新鲜粪便,通过灌胃移植到经广谱抗生素处理过的小鼠肠道中,提取2种猪粪便及其移植小鼠的盲肠内容物总基因组DNA,使用古菌通用引物对古菌16S rRNA的V4区进行PCR扩增,通过Illumina Hiseq测序平台对扩增产物进行高通量测序,使用QIIME等软件对测序序列进行分析统计。结果表明:金华猪和长白猪粪便及其移植小鼠盲肠内容物中的古菌主要包含3个门,分别为奇古菌门(Thaumarchaeota)、广古菌门(Euryarchaeota)和泉古菌门(Crenarchaeota),其中金华猪粪便中广古菌门的丰度高于长白猪;在属水平上主要包含4个已知属,优势属为餐古菌属(Cenarchaeum)。二者移植小鼠的盲肠内容物古菌结构,在门水平上,移植小鼠的奇古菌门比例占70%以上;奇古菌门的古菌几乎全部来源于餐古菌属;在门和属的水平上,金华猪和长白猪粪便移植小鼠的盲肠古菌结构无显著差异(P0.05),但基于操作分类单元(OTU)水平的主成分分析显示出很好的组内聚集。由此可见,奇古菌门的餐古菌属是金华猪和长白猪粪便和其移植小鼠盲肠中的优势古菌;金华猪粪便中广古菌门的丰度高于长白猪粪便,且二者移植小鼠盲肠内容物之间古菌结构在OTU水平上存在一定的差异。  相似文献   
98.
[目的]探讨草鱼肠道菌群与草鱼个体大小之间的相关性。[方法]采用DGGE方法对同一批孵化并在同一池塘中养殖的个体大小显著差异的草鱼肠道样品进行分析。[结果]无论大个体草鱼还是小个体草鱼,其肠道优势菌群均为厚壁菌门和变形菌门,但2组草鱼在其肠道菌群的结构和多样性等方面存在差异。大个体草鱼肠道中存在着更多比例的厚壁菌门以及具有纤维素降解能力的细菌,而小个体草鱼肠道中存在较多的潜在致病菌。[结论]草鱼肠道微生物可以作为内在因素影响草鱼的生长性能,这一结果也为进一步开发可促进草鱼生长性能的益生菌奠定了研究基础。  相似文献   
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