金针菇菇脚对肉鸡盲肠菌群及短链脂肪酸的影响

为探讨金针菇菇脚(Flammulina velutipes stembase,FVS)对肉鸡盲肠菌群及短链脂肪酸含量的影响,选用1d健康AA肉鸡270只,随机分成5个处理组,每组3个重复,每个重复18只。5个处理组分别为空白对照组(基础日粮)、抗生素阳性对照组(基础日粮+5mg/kg黄霉素)和3个FVS组(基础日粮中分别添加2%、4%和6%FVS)。在21和42d,每个重复选择3只屠宰,无菌采集盲肠内容物,提取细菌基因组总DNA,PCR扩增16srDNA V3区,采用变性梯度凝胶电泳技术结合聚合酶链式反应(PCR-DGGE)及条带的克隆测序分析盲肠细菌群的变化,同时采用聚类分析分析各试验组的多样性和相似性。用气相色谱仪检测盲肠中乙酸、丙酸、丁酸的含量。结果表明:1)与空白组相比,21和42d各FVS添加组条带数均高于空白组,且6%FVS添加组条带数显著升高(P0.05);2)与空白组相比,21和42d各FVS添加组聚类在一起,相似性系数均较高;3)21和42d,共性条带盲肠优势细菌主要是扭链胃球菌Ruminococcus]torques、厌氧发酵产氢细菌Acetanaerobacterium elongatum、甲酸芽殖菌Gemmiger formicilis、热产琥珀酸梭菌Clostridium]thermosuccinogenes、拟杆菌属Bacteroides sp.;而特异性条带主要是产丁酸菌Oscillibacter ruminantium、柔嫩梭菌Clostridium]leptum、Stomatobaculum longum、解多糖梭菌Clostridium]polysaccharolyticum、产乙醇杆菌Ethanoligenens harbinense strain YUAN-3、产丁酸盐罗氏菌Roseburia hominis、解纤维素梭菌Clostridium]cellulolyticum strain、乳酸发酵梭菌Clostridium]lactatifermentans等。4)与空白组相比,21和42d6%FVS添加组乙酸、丙酸、丁酸含量均显著升高,(P0.05)。以上结果提示:在肉鸡日粮中添加FVS可显著提高肉鸡盲肠菌群多样性,FVS可被有效利用产生降解多糖、纤维素和产酸的细菌,显著提高了短链脂肪酸的量,改善肠道菌的繁殖环境,改善动物肠道微生物菌群的结构,促进肉鸡健康生长。其中以6%FVS添加量效果最好。

Effect of supplementation of Flammulina velutipes stembase on the caecal microflora, short chain fatty acid of broiler

In this study, the effects of the Flammulina velutipes stembase(FVS) on the microflora, short chain fatty acid in caecum of Arbor Acres (AA) broiler chickens were evaluated.A total number of 270 one day-old broiler chickens were randomly divided into five dietary treatments with three replicates of each treatment.The control group was fed with basal diet (without the addition of antibiotics and FVS), antibiotic group was feed with the basal diet whit addition of 5 mg/kg flavomycin, three FVS groups were fed with the basal diet supplemented with different propotions of dried FVS at levels of 2%, 4% and 6%, respectively.On 21 and 42 d, three chickens of each replicates were slaughtered to take the caecum contents out under integral asepsis condition, and total genomic DNA of bacteria was extracted.The changes of intestinal flora were assayed by PCR-DGGE and cloning and sequencing of the bands.And the diversity and similarity of each test group were analyzed by cluster analysis.The content of acetic acid, propionate and butyrate in the appendix was detected by gas chromatography.The results showed that:The PCR-DGGE band numbers in three FVS treatment groups were all higher than in the control group, and especially, in 6% addition group the number of bands was significantly increased (P < 0.05).The similarity coefficient of 2%, 4% and 6% FVS supplementation groups was high both on both 21 and 42 d.Ruminococcus]torques, Acetanaerobacterium elongatum, Gemmiger formicilis, Clostridium] thermosuccinogenes, and Bacteroides sp. were commonly detected and Oscillibacter ruminantium, Clostridium] leptum, Stomatobaculum longum, Clostridium] polysaccharolyticum, Ethanoligenens harbinense strain YUAN-3, Roseburia hominis, Clostridium] cellulolyticum strain, Clostridium] lactatifermentans were specific.The acetic acid, propionic acid, and butyric acid contents in caecum were significantly increased (P < 0.05) in 6% FVS supplementation group on the 21, 42 day compared to control group.These results suggested that supplementation of FVS can significantly improve the diversity of the microflora, and increase the amount of short chain fatty acids, as well as improve the structure of intestinal microflora and promote the healthy growth of broiler chickens.And the best addition amount in the diet was 6%.