长顺绿壳蛋鸡肠道菌群结构及基因功能分析

Analysis of gut microbiota structure and gene function in Changshun green-shell laying hens

研究旨在明确长顺绿壳蛋鸡肠道菌群结构及功能。健康、体重无差异的20只27周龄长顺绿壳蛋鸡饲养35 d,随机选择4只,分别提取十二指肠、回肠和盲肠内容物的微生物总DNA,对16S rRNA进行高通量测序。结果显示:盲肠OTUs个数最多,其次为回肠,最少为十二指肠。盲肠的Ace指数、Chao-1指数和Shannon指数极显著高于十二指肠和回肠(P<0.01)。回肠的Ace指数和Chao-1指数显著高于十二指肠(P<0.05)。在门水平上,厚壁菌门为十二指肠(97.06%)和回肠(96.36%)的优势菌门;拟杆菌门(62.55%)和厚壁菌门(34.05%)为盲肠的优势菌门。在属水平上,乳杆菌属为十二指肠(94.133%)和回肠(95.273%)的优势菌属;拟杆菌属为盲肠(40.548%)的优势菌属。PICRUSt功能预测显示,肠道微生物基因主要富集于KEGG的新陈代谢(44.74%~49.34%)通路,其中盲肠营养物质代谢相关通路中富集基因相对丰度较高,如氨基酸代谢、能量代谢以及辅因子与维生素代谢等。研究表明,随着长顺绿壳蛋鸡肠道延伸,菌群多样性程度明显增加,且盲肠菌群的营养代谢作用更为活跃。

The purpose of the study was to clarify the structure and function of the intestinal flora of Changshun greenshell laying hens. 20 healthy 27-week-old Changshun green-shell hens with no difference in body weight were reared for35 d, and four hens were randomly selected. Total microbial DNA was extracted from the contents of the duodenum, ileum,and cecum, respectively, and high-throughput sequencing of 16S rRNA was performed. The results showed that the largest number of OTUs was in the cecum, followed by the ileum, and the least in the duodenum. The Ace index, Chao-1 index and Shannon index of cecum were extremely higher than those of duodenum and ileum(P<0.01). The Ace index and Chao-1 index of ileum were significantly higher than those of duodenum(P<0.05). At the phylum level, Firmicutes were the predominant phyla of duodenum(97.06%) and ileum(96.36%), Bacteroidetes(62.55%) and Firmicutes(34.05%) were the predominant phyla of cecum. At the genus level, Lactobacillus was the dominant species in the duodenum(94.133%) and ileum(95.273%), Bacteroides was the dominant species in the cecum(40.548%).PICRUSt functional prediction showed that gut microbial genes were mainly enriched in the metabolic(44.74%~49.34%) pathway of KEGG, the relative abundance of enriched genes in caecal nutrient metabolism-related pathways was higher, such as amino acid metabolism, energy metabolism, cofactor and vitamin metabolism, etc. The study indicates that with the extension of the intestine of Changshun green-shelled hens, the diversity of the flora increases significantly, and the nutritional metabolism of the cecal flora is more active.