补饲精料对大青山绒山羊瘤胃细菌及产甲烷菌多样性的影响

Effect of supplementary feeding on the diversity of rumen bacteria and methanogens in grazing Daqingshan cashmere goats

本研究利用高通量测序技术,对放牧和补饲条件下大青山绒山羊瘤胃细菌及甲烷菌多样性进行了分析。试验选用10只1岁平均体重为(38.2±1.6)kg的健康大青山绒山羊(羯羊),分成放牧组和补饲组。29 d试验结束后,从抽取的瘤胃液中提取微生物DNA,对瘤胃细菌、甲烷菌的16S rDNA序列V3至V4区进行HiSeq测序。结果表明:在门水平上,与放牧组相比,补饲显著提高了拟杆菌门和变形菌门丰度,显著降低了厚壁菌门和互养菌门的比例;在科水平上,普雷沃氏菌科(40.73%、62.77%)为主要细菌类别,补饲精料后其丰度显著提高,而显著降低了韦荣球菌科、瘤胃球菌科、理研球菌科和互养菌科。补饲显著增加了甲烷杆菌科而降低了甲烷八叠球菌科的丰度;在属水平上甲烷短杆菌属表现出绝对优势,补饲后显著升高,但甲烷微球菌属显著降低,其他甲烷菌属无显著差异。研究表明,补饲精料降低了瘤胃内与纤维分解相关细菌的丰度,产甲烷菌丰度在科、属水平上受补饲的影响也存在差异,但放牧与补饲条件下大青山绒山羊瘤胃中细菌和产甲烷菌的优势菌群并未发生变化。

This study was to analyze,using high-throughput sequencing technology,the diversity of rumen bacteria and methanogens in Daqingshan cashmere goats under natural grazing(NG)and natural grazing with supplementary feeding conditions(GS).Ten healthy Daqing shan cashmere goats with similar health conditions were selected and divided into two groups with 5 heads per group according to their body weight(38.2±1.6)kg.The experiment lasted for 29 days.At day 29,the microbial DNA was extracted from the rumen fluid of the animals,and the 16 S rDNA sequence V3-V4 region of the rumen bacteria and methanogens was sequenced by HiSeq.The results showed as follows:1)At the phyla level,compared with NG,GS raised the abundance of Bacteroidetes and Proteobacteria,but reduced that of the Firmicutes and Synergistetes;and at the family level,the dominant bacteria were Prevotellaceae(40.73%,62.77%).Compared with NG,GS lowered the abundance of Veillonellaceae,Ruminococcaceae,Rikenellaceae and Synergistaceae.2)The ruminal methanogen community of in Daqing shan cashmere goats was dominated by Methanobacteriaceae and Methanobrevibacter.After supplementation,the above two bacteria were significantly increased,but the M.mobilis was significantly reduced.In summary,supplementary concentrate feed reduced the abundance of bacteria associated with fiber breakdown in the rumen;also at the family and genus levels,the supplementary feeding had an effect on the abundance of methanogens.However,there was no variation in the abundance of the dominant bacteria and methanogens in the rumen of the goats under grazing and supplementary feeding conditions.