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31.
Runqi Fu Chan Liang Daiwen Chen Hui Yan Gang Tian Ping Zheng Jun He Jie Yu Xiangbing Mao Zhiqing Huang Yuheng Luo Junqiu Luo Bing Yu 《Journal of animal physiology and animal nutrition》2021,105(5):898-907
The present study investigated the effects of Bacillus coagulans and yeast hydrolysate supplementation on growth performance, immune response and intestinal barrier function of weaned piglets. Twenty-four weaned piglets with an average body weight (BW) of 6.89 ± 0.15 kg were divided into four diets for 28 days. The treatments were basal diet (control), basal diet supplemented with antibiotic (20 mg/kg colistin sulphate and 40 mg/kg bacitracin zinc, AT), probiotics (400 mg/kg Bacillus coagulans ≥5 × 109 CFU/g, BC) or yeast hydrolysate (5000 mg/kg yeast hydrolysate, YH). Average daily gain (ADG) and average daily feed intake (ADFI) were improved by AT and YH diets (p < 0.05), while BC diet only increased ADG (p < 0.05). The complement 3 (C3), lysozyme (LZM) and tumour necrosis factor-α (TNF-α) concentrations in serum were increased in BC diet (p < 0.05). Feeding AT and YH caused the increase of jejunal villus height (p < 0.05), and a higher ratio of villus height/crypt depth was observed in AT, BC and YH groups (p < 0.05). The mRNA expression of zonula occludens-1 (ZO-1) in jejunal mucosa was up-regulated by AT, BC and YH diets (p < 0.05). Dietary AT, BC or YH inclusion decreased the interleukin-1β (IL-1β) concentration and TNF-α mRNA expression (p < 0.05), and YH supplementation even down-regulated toll-like receptor 4 (TLR4) and CD14 expressions (p < 0.05). In summary, the dietary administration of BC or YH both improves growth performance through promoting the intestinal barrier function, indicating both of them can serve as potential alternatives to antibiotics growth promoters for the piglet production. 相似文献
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To investigate the species of cellulase-producing Bacillus in yak rumen,10 samples of rumen content were aseptically collected from 10 adult Maiwa yaks to isolate the heat-resistant Bacillus by water bath at 80 ℃ for 20 min.The cellulase-producing strains were screened using the CMC-Na medium and Congo red staining.The 16S rRNA gene sequence of those cellulose-producing strains were amplified and sequenced.The results showed that 64 strains were isolated from the 10 samples.Total 23 strains were identified as cellulase-producing bacillus,including 16 strains of Bacillus cereus,7 strains of Bacillus thuringiensis.Furthermore,phylogenetic analysis showed that the 16 Bacillus cereus strains were clustered into two branches:One isolate was clustered into a branch alone,the other 15 isolates were clustered into a branch which clustered into 5 small branches,showing that there was certain genetic diversity in the isolates of Bacillus cereus.And all 7 Bacillus thuringiensis strains were clustered into a branch.Hence,the results layed the foundation of investigating the species of cellulase-producing Bacillus in yak rumen and developing probiotics special for yak. 相似文献
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WANG Lei LV Yang ZHANG Yue XIE Jia-qian ZHAO Di YAN Li-qiong MEI Hui-min WANG Lei YI Dan CHEN Hong-bo DING Bin-ying HOU Yong-qing WU Tao 《中国畜牧兽医》2016,43(5):1355-1360
The probiotics tested in the experiment were isolated from the intestinal of weaning piglets.The isolated probiotics and E.coli K88 were inoculated into the culture of intestinal porcine epithelial cell-1 (IPEC-1).The activity of lactate dehydrogenase (LDH) in the supernatant was measured after incubating for 2.5 h.At the same time, the probiotics and E.coli K88 were co-cultured in vitro, the number of E.coli K88 was counted and the probiotics which could be resistant to the E.coli K88 were selected 2.5 h later.The results showed that the Lactobacillus casei and Bacillus coagulans could significantly reduce LDH activity (P<0.05), decrease the damage of E.coli K88; Bacillus coagulans could inhibit the growth of E.coli K88.At the same time, Bacillus coagulans could resist high temperature, acid and bile salt.The results showed that Bacillus coagulans strains had great potential as the application of probiotics strains.The methods could be used as a model of screen probiotics which could inhibit the growth of E.coli K88 in vitro. 相似文献
34.
XIE Quan-xi ZHANG Jian-mei YU Jia-min QI Xiu-ye XU Hui XU Hai-yan GU Wei 《中国畜牧兽医》2016,43(6):1523-1529
This experiment was designed to study the complex of Lactobacillus rhamnosus fermented herbal and Bacillus subtilis on White Feather broiler immunity performance and impact of Escherichia coli infection.360 one-day-old broiler chickens were randomly divided into 3 groups with 4 replicates in each group and 30 chickens per replicate.The pretrial period lasted for 7 d,and the experiment lasted for 35 d.The chickens in the group Ⅰ(positive control group) and group Ⅱ(negative control group)were all only fed a basal diet,group Ⅲ was test group,by additive 1% fermented herbal preparations,groups Ⅱ and Ⅲ were intraperitoneal injection of 1 mL E.coli at 35 d,broiler mortality,immune organ index,cecalmicroflora content,immunoglobulin levels,IL-2 and IL-6 content were tested.The results showed that injection of E.coli caused massive death of chickens,group Ⅱtook up to 75.00%,it was significantly higher than groups Ⅰ and Ⅲ (P < 0.05),the mortality in group Ⅲ was significantly lower than group Ⅱ(P < 0.05),was only 23.33%.Injection of E.coli maked spleen index and thymus index of group Ⅱincreased significantly (P < 0.05),the spleen index and thymus index of groups Ⅰ and Ⅲ were no significant difference (P > 0.05).E.coli counts was significantly decreased after injectionin group Ⅲ (P < 0.05),but the number of intestinal Lactobacilli of group Ⅲ was significantly increased (P < 0.05),and inhibited the propagation of E.coli,the counts of E.coli in groups Ⅰ and Ⅲ were no significant difference (P > 0.05).At 42 d,the sIgA of the intestinal fluid in group Ⅲ were higher than that of groups Ⅰ and Ⅱ with 11.99% and 36.56%,respectively(P < 0.05).The serum IgG concentrations of group Ⅲ was higher than that of groupsⅠand Ⅱwith 14.68% and 28.15%,respectively(P < 0.05).At 42 d,the IL-2 content of group Ⅱ was the lowest,it was significantly lower than group Ⅲ(P < 0.05),the IL-6 of group Ⅲ was significantly lower than group Ⅱ(P < 0.05). 相似文献
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36.
为明确60Co-γ亚不育剂量辐照对小菜蛾Plutella xylostella种群数量动态变化的影响,构建小菜蛾种群动态变化模型,在实验室条件下通过建立小菜蛾生命表获得种群特征参数、个体生理指标,预测亚不育剂量辐照对小菜蛾种群的影响。结果显示,亚不育剂量辐照组的羽化率显著高于完全不育剂量组,与空白对照组无显著差异,各处理羽化率无性别差异,亚不育剂量辐照组F1代孵化率显著低于空白对照组。亚不育剂量辐照组种群各阶段发育历期、存活率及繁殖力生命指标低于空白对照组。小菜蛾亚不育剂量辐照组世代平均历期(19.90 d)、世代净生殖率(2.35)、周限增长率(1.04 d-1)、内禀增长率(0.04 d-1)均低于空白对照组,而种群加倍时间(16.16 d)高于空白对照组。空白对照组世代平均历期、每日单雌产卵量与产卵时间均长于亚不育剂量辐照组。辐照组与对照组种群生命表参数对比,表明亚不育剂量降低了小菜蛾种群世代数和幼虫期的个体存活率,使F1代雌虫个体数减少。 相似文献
37.
青枯病(bacterial wilt)是生姜上的一种细菌土传毁灭性病害,化学防治易污染环境且常规化学药剂很难在土壤中起到持续控病的作用,生物防治是其理想的防治方法。为开发对生姜青枯病有效的生防措施,对从生姜根际土壤中分离的一株生防细菌YB-3进行了鉴定,并对其生物学特性及生防效果进行了研究,以丰富生防菌株资源库。采用抑菌圈法筛选拮抗细菌,对效果最好的拮抗菌株做盆栽试验,测定其对生姜青枯病的防治效果,根据形态特征、生理生化特性以及16S rDNA序列对筛选得到的优良菌株进行鉴定。试验结果表明,该拮抗菌在平皿上对青枯菌的抑菌率为50.67%,盆栽试验对青枯病的防治效果为60.86%;经16S rDNA序列分析,并结合形态学和生理生化特征,将菌株YB-3鉴定为巨大芽胞杆菌Bacillus megaterium。YB-3是一株具有开发利用价值的姜青枯病生防菌株。 相似文献
38.
本试验旨在研究凝结芽孢杆菌对热应激肉鸡生长性能及肠道消化与吸收功能的影响。选择320只28日龄健康爱拔益加(AA)肉公鸡,随机分为5个组,每组8个重复,每个重复8只。常温对照组(TC组)肉鸡饲养于(22±1)℃的常温环境,饲喂基础饲粮;热应激组(HS组)肉鸡饲养于(34±1)℃的高温环境,饲喂基础饲粮;热应激试验组肉鸡饲养于(34±1)℃的高温环境,分别饲喂在基础饲粮中添加0.2×107(HS-BC0.2组)、1.0×107(HS-BC1.0组)、5.0×107CFU/g(HS-BC5.0组)凝结芽孢杆菌的试验饲粮。试验期14 d。结果表明:与TC组相比,HS组的末重、平均日增重(ADG)、平均日采食量(ADFI),干物质和粗蛋白质表观代谢率,空肠食糜总淀粉酶和总蛋白酶酶活,空肠绒毛高度、绒毛高度/隐窝深度以及空肠钠/葡萄糖协同转运蛋白1(SGLT1)、基础氨基酸转运载体(r-BAT)、y+L氨基酸转运载体-1(y+LAT1) mRNA表达量均显著降低(P<0.05),料重比(F/G)显著增加(P<0.05)。与HS组相比,HS-BC1.0和HS-BC5.0组的ADG、粗蛋... 相似文献
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