民猪与大白猪肠道菌群的比较研究

Comparative study on intestinal florabetween Minzhu and Large white pigs

民猪是我国一个著名的地方猪种,属于脂肪型猪种。而大白猪起源于欧洲,是瘦肉型猪种。通过比较这2个不同猪种间肠道微生物菌群的差异,分析它们在消化吸收上的异同点。首先针对16S r DNA V4区设计引物,对来自于5头大白猪和5头民猪的粪便基因组进行PCR扩增,利用Illumina Hiseq2000测序平台进行测序,数据经优化整理后,进行OTU聚类分析,并在门、纲、目、科和属共计5个水平上进行分类学统计。结果表明：共获得421~460 bp序列298 768条,占总数的99.98%。2组间共有OTU 885个,大白猪特有OTU 69个,民猪特有OTU 221个。共检测到25个门,其中拟杆菌门（Bacteroidetes）、厚壁菌门（Firmicutes）、螺旋菌门（Spirochaetae）和变形菌门（Proteobacteria）占优势,民猪和大白猪之间具有大致相同的门水平分布。在检测到的207个属中,普氏菌属（Prevotella）和密螺旋体属（Treponema）的相对丰度值在2个猪种内均较高。而大白猪的厌氧弧菌属（Anaerovibrio）和梭菌属（Clostridium）分别比民猪猪高出4.5倍和3.4倍,民猪的纤维杆菌属（Fibrobacter）、螺旋体属（Spirochaeta）和密螺旋体属（Treponema）比大白猪分别高出3.7倍、1.6倍和1.7倍。由此推测,民猪肠道内纤维杆菌属的高表达可能与其易消化粗纤维饲料有关。

Minzhu pig is one of the famous indigenous pigs in China,which is a kind of fatty pig breed.Large white pig is originated in Europe and is a kind of lean pig breed.Through comparing the differences of the intestinal flora in two different pig breeds,we analyze the similarities and differences of them in the digestion and absorption.At first,primers were designed according to the V4 region of 16S rDNA.DNA was extracted from feces of five Minzhu and five Large white pigs,respectively.PCR was conducted by these DNA and the sequence was sequenced by Illumina Hiseq2000.After optimizing the data,OTU cluster analysis was carried out,and the classification statistics were carried out at 5 levels in the phylum,class,order,family and genus.298,768 reads of 421~460 bp length were obtained,which account for 99.98% of the total.Two groups shared 885 OTU,69 OTU were specific in Large white pigs and 221 OTU were specific in Minzhu pigs.A total of 25 phyla were detected,in which Bacteroidetes,Firmicutes,Spirochaetae and Proteobacteria were dominant.The distribution pattern of Minzhu and Large white pigs were similar in phylum levels.Further analysis showed that the relative abundance of Prevotella and Treponema were all higher in these two breeds.While,the Anaerovibrio and Clostridium in Large white pigs were higher than that of Minzhu pigs by 4.5-fold and 3.4-fold,respectively.The relative abundance of Fibrobacter,Spirochaeta and Treponema in Minzhu pigs was higher than that of Large white pigs by 3.7-fold,1.6-fold and 1.7-fold,respectively.It is speculated that the higher relative abundance of Fibrobacter in Minzhu may be related to its digestible crude fiber feed.