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991.
This study was conducted to investigate the effects of carvacrol and thymol on the relative abundance of colonic microorganisms in weaned piglets and their metabolic pathways.A total of sixty four 28-day-old (8.5 kg±1.0 kg) weaned piglets were divided into 4 groups with 16 replicate of 1 piglet:Group A (control group,basal diet),group B (basal diet+20 g/T carvacrol),group C (basal diet+20 g/T thymol),and group D (basal diet+20 g/T carvacrol-thymol blend (mass ratio 2:1)).The experiment lasted 30 d.The sequencing was taken based on the Illumina HiSeq sequencing platform,and using paired-end sequencing (Paired-End) method.Perform species annotation and abundance were analysized by clustering OTUs,and alpha diversity analysis、beta diversity analysis、significant species difference analysis and functional gene prediction analysis were further conducted.The results showed as follow:①The colonic microorganisms biodiversity of the experimental groups were significantly higher than that of control group (P<0.05).②The relative abundance of Firmicutes in the colon of group D was extremely significantly higher than that of control group (P<0.01),significantly higher than groups B and C (P<0.05),the relative abundance of Bacteroidetes was significantly higher than that of control group and group C (P<0.05),and the relative abundance of Epsilonbacteraeota,Spirochaetes and Proteobacteria were extremely significantly lower than that of control group (P<0.01).The relative abundance of Campylobacter in the colon of group D was extremely significantly lower than that of control group (P<0.01),that of Rikenellaceae_RC9_gut_group in group D was significantly higher than that of group B (P<0.05),that of Roseburia in group D was extremely significantly higher than that of group A (P<0.01),that of Helicobacter was extremely significantly lower than that of group A (P<0.01).③The lipid metabolism level of colonic microorganisms in group D was extremely significantly higher than that of control group (P<0.01),and colonic microbial carbohydrate metabolites,biosynthetic of other secondary metabolites and other amino acid metabolism level were significantly higher than that of control group (P<0.05),and energy metabolism level of colonic microorganisms was extremely significantly lower than that of control group (P<0.01).In conclusion,under the condition of this experiment,dietary supplementation with 20 g/t carvacrol-thymol improved the microbial community structure of colonic microorganisms in weaned piglets.The relative abundance of colonic beneficial bacteria was increased,the relative abundance of colonic harmful bacteria was decreased,and positively affected the metabolic function of colonic microorganisms. 相似文献
992.
选用42窝406头不同品种(长白×大约,长白,杜×长×大)的乳猪分成两组进行了两次小试筛选和1次中试验证,与占领国内乳猪料市场的某中外合资企业乳猪料进行对比试验。中试试验各项饲养性能指标分别为:0~56日龄日增重试验组327.86g,对照组316.25g,试验组比对照组提高3.67%,0~56日龄料肉比分别为0.94∶1和0.98∶1,试验组比对照组降低4.08%,育成率均为99.5%。上述指标差异均不显著(P>0.05),但试验组较对照组降低成本10.47%,提高经济效益13.86%。 相似文献
993.
选择 2 8日龄断奶杜长大三元杂交仔猪 60头 ,随机分为 4组 ,每组 15头 ,分别饲喂以总氨基酸或可消化氨基酸为基础设计饲粮 ,研究其对仔猪生产性能和经济效益的影响。结果表明 :在可消化氨基酸相同条件下 ,适当降低饲粮粗蛋白质水平 ,并不影响仔猪生产性能 ( P>0 .0 5) ,且有利于控制腹泻和提高经济效益 ,但总氨基酸含量相同饲粮 ,其生产性能差异显著 ( P〈0 .0 5)。故生产上以可消化氨基酸设计日粮比总氨基酸设计日粮更合理 ,更接近仔猪对氨基酸需要。 相似文献
994.
995.
本试验采用2×2析因设计,选用96头(28±2)d的(大白×长白)断奶仔猪[平均体重(7.24±0.36)kg],按体重相近原则随机分为4组,第Ⅰ组为对照组,饲喂基础日粮;第Ⅱ组为脂多糖(LPS)免疫应激组,在试验开始7d后注射100μg/kg的LPS;第Ⅲ组为谷氨酰胺(Gln)组,饲喂含Gln浓度为1.2%的日粮;第Ⅳ组为Gln+LPS免疫应激组,饲喂含Gln浓度为1.2%的日粮,7d后注射100μg/kg的LPS,研究谷氨酰胺对免疫应激仔猪肠道指数的影响。试验期14d。结果显示:LPS免疫应激极显著降低了免疫应激仔猪的小肠指数(P0.01),添加Gln极显著提高了免疫应激仔猪的小肠指数和大肠指数(P0.01)。日粮类型与应激的交互作用对仔猪的小肠指数和大肠指数的影响均不显著(P0.05)。 相似文献
996.
997.
I. Nochta V. Halas J. Tossenberger L. Babinszky 《Journal of animal physiology and animal nutrition》2010,94(6):747-756
Several studies report that dietary mannan‐oligosaccharides (MOSs) improve the growth performance of piglets, however, only a few studies focus on nutrient digestibility. The aim of the study was to investigate the effect of dietary MOS on ileal digestibility of nutrients and on N‐balance and growth performance of piglets weaned at 28 days of age. Three experiments were conducted: a digestibility trial with a total of 30, simple T‐cannulated piglets (Exp. 1), a N‐balance trial with a total of 48 intact piglets (Exp. 2) and a performance trial with a total of 324 piglets (Exp. 3). In Exp. 1 and 2, the same five dietary treatments were carried out by supplementing the basal diet with 0, 1, 2, 4 g MOS or with 0.2 g antibiotic growth promoter (AGP, Avilamycin) per kg of diet. In Exp. 3, three dietary treatments were used as follows: the basal diet was supplemented no additive, 2 g MOS or 0.2 g AGP (Avilamycin) per kg of diet. Dietary MOS (2 or 4 g/kg) enhanced the ileal digestibility of crude protein similar to antibiotics. Addition of 1 g/kg MOS significantly increased the digestibility of Ca and P by 8.4% and 7.7% units, respectively; however, further increment did not enhance the absorption. Addition of 1 or 2 g/kg MOS significantly increased the ileal digestibility of lysine, methionine, cystine and threonine with the same magnitude or even more than the AGP. In our study, MOS supplementation had no influence on N‐balance and growth parameters. Because of the better apparent ileal digestibility of certain nutrients, however, the protein, lysine, methionine, cystine, threonine, Ca and P contents of the diet can probably be reduced without weakening the rearing performance of piglets, when the diet is supplemented with 2 g/kg MOS. 相似文献
998.
999.
寡聚糖对仔猪肠道菌群及生长性能影响的研究 总被引:33,自引:1,他引:32
试验研究了饲料中添加寡聚糖对哺乳仔猪和断乳仔猪生产性能和肠道菌群的影响。选择了 10窝仔猪 ,随机分为 5组 ,每组两窝。第 1组 (对照组 )日粮为以玉米、豆粕为主的基础日粮 ,第 2 ,3,4 ,5组日粮分别在基础日粮中添加 0 .0 5% ,0 .10 % ,0 .2 0 % ,0 .35%的寡聚糖。试验分为两个阶段 ,7~ 2 8日龄断乳 ,断乳~ 56日龄结束。 2 1日龄取粪样进行大肠杆菌、 p H、水分测定 ,4 2日龄每组屠宰 3头仔猪取盲肠、结肠、直肠进行双歧杆菌、大肠杆菌、 p H、水分测定。结果表明 ,在哺乳阶段 ,寡聚糖能显著 ( P <0 .0 5)降低粪便中的大肠杆菌数量和 p H,但对哺乳仔猪的生产性能和粪便中的水分含量影响不显著 ( P >0 .0 5)。在断乳后 ,0 .10 %的寡聚糖添加量能显著( P <0 .0 5)提高仔猪的日增重、降低料肉比、减少腹泻率的发生 ,0 .35%的寡聚糖添加量对仔猪的生产性能没有影响。 0 .10 %与 0 .2 0 %的寡聚糖添加量能显著 ( P <0 .0 5)抑制直肠中大肠杆菌的增殖 ,促进结肠中双歧杆菌的增殖。寡聚糖对盲肠、结肠、直肠中的 p H的影响差异不显著 ,但能显著 ( P <0 .0 5)降低直肠中的水分含量。 相似文献
1000.
为了避免个体差异,在2窝仔猪中各选择6头,共12头仔猪随机分成对照组(6头)和试验组(6头),在40日龄时分别肌注卡介苗(试验组)和等量生理盐水(对照组),于接种前(0d)和接种后3、7、10、14d采血检测,研究结果表明,卡介苗能在3d内提高断卫猪淋巴细胞转化率和血清杀菌能力,分别在第7d和第3d达到高峰,此后,于第10d和第7d开始迅速降低,而对白细胞总数和活性T淋巴细胞则无显著影响。试验结果表明,卡介苗能显著增强断乳仔猪的细胞免疫水平和机体的抗病能力。 相似文献