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41.
本试验旨在研究发酵前后芹菜汁的主要功能成分变化和芹菜发酵液对葡聚糖硫酸钠(DSS)诱导的小鼠溃疡性结肠炎(UC)的防治及免疫调节作用。选取50只4周龄雄性C57BL/6小鼠随机分为空白组、模型组及低、中、高浓度芹菜发酵液组,每组10只。按10 μL/g BW的剂量标准给空白组和模型组小鼠灌胃无菌生理盐水,其他组小鼠则灌胃不同浓度的芹菜发酵液,持续7 d。从第8天开始,除空白组自由饮用无菌水外,其余组连续7 d自由饮用3% DSS溶液;在此过程,每日称量体重,进行疾病活动指数(DAI)评分。在第14天,通过摘眼球取血法获得全血,随后脱颈处死小鼠,解剖取出结肠组织测量长度并通过苏木素-伊红(HE)染色法制作病理切片,进行病理学分析。以流式细胞仪分选技术检测外周血中CD4+/CD8+T淋巴细胞比值,以酶联免疫吸附法(ELISA)检测血清中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、γ-干扰素(IFN-γ)和IL-10的含量。结果表明:①芹菜汁经发酵后,总酸、总糖、总多酚、类黄酮、维生素C和超氧化物歧化酶(SOD)等多种活性成分的含量均显著增加(P<0.05)。②与模型组相比,芹菜发酵液高浓度组能减少DSS引起的小鼠体重损失(P<0.01)、结肠缩短(P<0.01)和DAI降低(P<0.05)。③组织病理学分析结果表明,各发酵液组的UC症状均得到不同程度改善,肠腺结构相对完整,杯状细胞轻微减少,仅有少量淋巴细胞和中性粒细胞浸入。④流式细胞仪分析结果显示,相较于模型组,发酵液组全血CD4+/CD8+T淋巴细胞比值极显著升高(P<0.01)。⑤ELISA检测结果显示,与模型组相比,芹菜发酵液组的IL-6、TNF-α和IFN-γ含量极显著下调(P<0.01),IL-10的含量极显著上调(P<0.01)。综上,芹菜汁经发酵后主要功能活性成分均得到显著提高,并且发酵芹菜液对DSS诱导的小鼠UC具有一定的防治和免疫调节作用,其作用机制可能与维持外周血中CD4+与CD8+T淋巴细胞平衡,以及抑制促炎症因子(TNF-α、IL-6和IFN-γ)表达,促进抗炎症因子(IL-10)表达有关。 相似文献
42.
综述了非离子表面活性剂对反刍动物瘤胃微生物数量、酶活性、瘤胃发酵特性、饲料消化率和生产性能等方面的影响作用以及与其他饲料添加剂的互作效应,并就其作用机制进行了阐述。 相似文献
43.
李玉琴黄新高鹏翔赵小博王慧蒋林树 《动物营养学报》2023,(1):311-322
This experiment was conducted to study the effects of Bacillus amylolyticus on rumen dry matter digestibility, fermentation parameters and metabolites of dairy cows. Experiment 1: six dairy cows with permanent fistula and had the similar parity (2 to 3 fetuses), body weight [(662 ±57) kg], lactation days [(160 ± 22) d] and milk yield [(36.1 ±3.8) kg / d], were randomly divided into 3 groups with 2 cows per group. Using 3 ×3 Latin square design, each group was extra fed 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, the trial period was 3 periods, 13 days for each period, including 10 days for the pre-trial period and 3 days for the trial period. At the beginning of the trial period, the rumen dry matter digestibility of cows was measured by nylon bag method. Experiment 2: thirty dairy cows with similar parity [(2.5 ±0.3) fetuses], initial body weight [(559.2 ± 7. 4) kg], milk yield [(35. 2 ± 1. 5) kg / d] and lactation days [(99 ± 22) d] were randomly divided into three groups with 10 cows in each group. Cows in the 3 groups were extra fed with 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, respectively. The pre-trial period was 10 days and the trial period was 42 days. The rumen fluid was collected on the last day of the trial period, and the rumen fermentation parameters and metabolites were determined. The results showed as follows: compared with the control group, 1) supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 12, 24, 36, 48 and 72 h (P <0.05), supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 36 and 48 h (P <0.05); 2) supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid, butyric acid, isovaleric acid, valeric acid, total volatile fatty acid and microbial protein in the rumen of dairy cows (P < 0. 05), supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid and isovaleric acid in the rumen of dairy cows and significantly reduce the rumen acetic acid / propionic acid (P < 0. 05), supplementary feeding of 5 ×109 and 5 ×1010 Bacillus amylolyticus had no effects on rumen pH and ammonia nitrogen content (P >0.05); 3) eleven metabolic pathways related to differential metabolites were detected, and ascorbic acid and alginate metabolism were significantly enriched (P < 0. 05) . In conclusion, Bacillus amylolyticus can increase the rumen dry matter digestibility, and improve the rumen fermentation function of dairy cows by affecting the content of rumen metabolites. By comprehensive analysis, supplementary feeding of 5 × 109 CFU / d Bacillus amylolyticus can achieve better effect. © 2023 Authors. All rights reserved. 相似文献
44.
This study was conducted to investigate the effects of compound p1ant nutrients (CPN) on rumen fermentation parameters, rumen microbiota and fatty acid composition of longissimus dorsi musc1e in finishing sma11 tai1 Han sheep. Sixteen 4-month-o1d finishing sma11 tai1 Han sheep with an initia1 body weight (BW) of (24.18±0.31) kg were random1y divided into two groups, name1y, with 8 rep1icates per group and 1 sheep per rep1icate. The sheep in the contro1 group were fed a basa1 diet, whereas the sheep of the contro1 group (CPN group) was fed the basa1 diet supp1ementation with 3‰ CPN. The experiment 1asted for 97 days after 7 days adaption. The resu1ts showed as fo11ows: compared with the contro1 group, 1) adding CPN decreased the concentration of ammonia nitrogen (NH3-N) (P<0.05); 2) CPN supp1ementation affected beta diversity of rumen microbiota; 3) the re1ative abundance of Acidobacteriota, Erysipe1otrichaceae_UCG-002, Lactobacillus, and Megasphaera were enhanced by adding CPN (P<0.05), whereas, the re1ative abundance of Bacteroidetes and Prevotella was 1ower (P<0.05); 4) the supp1ementation of CPN had no significant effect on fatty acid composition of longissimus dorsi musc1e of fattening sma11-tai1ed Han sheep (P>0.05); 5) the contents of tota1 MUFA, C18:1n9c, C14:1, C16:1, C18:2n6c, C18:3n3 and n-3PUFA in the longissimus dorsi musc1e were corre1ated with the re1ative abundance of Megasphaera, Erysipe1otrichaceae_UCG-002, Succiniclasticum and Ruminococcus (P<0.05). In conc1usion, CPN can regu1ate the rumen microbiota structure and reduce the rumen NH3-N concentration of fattening sma11-tai1ed Han sheep. In production practice, CPN can be used as a rumen eco1ogica1 regu1ator. © 2023 Authors. All rights reserved. 相似文献
45.
通过Rusitec-s体外发酵系统研究不同粒度猫尾草对羔羊体外发酵参数与微生物数量的影响,选取6种不同粒度(1.00、2.36、3.35、4.75、8.00和12.50 mm)的猫尾草作为试验饲粮的纤维来源,按照猫尾草的粒度将试验分为6个处理组,每个处理4个重复,利用Rusitec-s型人工瘤胃模拟装置进行48 h体外发酵,测定养分降解率、发酵参数及发酵液中6种微生物菌群的拷贝数。结果表明:与其他处理组相比,2.36 mm组显著提高了体外中性洗涤纤维降解率(IVNDFD)、丁酸、异丁酸、戊酸、异戊酸摩尔比和溶纤维丁酸弧菌(B. f)数量(P<0.05),且显著降低总产甲烷菌(TMe)数量(P<0.05)。总菌(TB)与氨态氮(NH3-N)浓度、乙酸摩尔比呈正相关(R2=0.84,P=0.038;R2=0.88,P=0.021);B. f数量与丙酸摩尔比呈正相关(R2=0.82,P=0.045),且与pH呈负相关(R2=-0.98,P=0.001);TMe数量与体外粗蛋白质降解率(IVCP... 相似文献
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48.
有机废水产酸发酵的生理生态学分析 总被引:9,自引:0,他引:9
通过对产酸发酵细菌细胞内生物物理化学及发酵途径分析表明,控制生物产酸发酵类型的主要因素有NADH/NAD+平衡和发酵产物酸性末端数量。根据微生物的生理生态学原理及试验结果分析,证实所发现的乙醇型发酵优于丁酸型发酵和丙酸型发酵。此外,还对氢分压与丙酸积累的相关性提出新的见解。 相似文献
49.
奶牛养殖场粪污处理沼气工程技术与模式 总被引:9,自引:3,他引:9
本文综述了国内外奶牛养殖场沼气工程技术应用现状,分析了奶牛粪沼气发酵潜力和三种主要沼气发酵工艺的技术特点. 相似文献
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