柔嫩艾美耳球虫感染对鸡盲肠菌群的影响

Effect of Eimeria tenella infection on the caecal flora of chickens

将60只健康罗曼粉鸡随机分为正常组和模型组,每组30只,模型组灌服1×10^(4)个孢子化卵囊进行人工复制鸡球虫病模型,正常组灌服等体积生理盐水,感染5 d,剖杀试验鸡,无菌采集鸡盲肠内容物,并通过Illumina PE250型高通量测序仪对肉鸡盲肠内菌群进行16SrDNA基因V3~V4可变区检测,对肠道菌群可操作分类单元(OTUs)数、α多样性、β多样性及差异菌门与菌属进行综合性分析与评价,探究柔嫩艾美耳球虫感染对鸡盲肠菌群结构和多样性的影响。结果表明:与正常组相比,感染柔嫩艾美耳球虫后鸡肠道菌群的OTUs数、Chao1指数极显著降低,Shannon指数显著降低,Simpson指数显著升高;门水平上,模型组变形菌门的相对丰度极显著升高,而厚壁菌门的相对丰度显著降低,拟杆菌门和柔膜菌门的相对丰度显著降低;属水平上,正常组的优势菌属为拟杆菌属、瘤胃菌属-UCG014、副拟杆菌属,而模型组瘤胃球菌属-uncultured、球藻菌属、埃希菌-志贺菌属相对丰度极显著升高。可见,艾美耳球虫破坏了盲肠菌群的完整性,促进潜在致病菌的建立和生长,尤其使埃希菌-志贺菌属大量繁殖,快速生长。

60 healthy Roman powder chickens were randomly divided into normal group and model group,30 in each group with 30 chickens in each group.The model group was fed with 1×10^(4)sporulated oocysts to artificially replicate the chicken coccidiosis model.The normal group was treated with normal saline.Five days after infection,the test chickens were sacrificed,the contents of the chicken cecum were collected aseptically,and the 16S rDNA gene V3-V4 variable region of the intestinal flora of the cecal contents of broilers was detected by Illumina PE250 high-throughput sequencer.Comprehensive analysis and evaluation of the number of operable taxonomic units(OTUs)of the intestinal flora,αandβdiversity,as well as differences in phylum and genus,to study the effect of Eimeria tenella infection on the structure and diversity of chicken cecal flora.The results showed as follows:after infection with Eimeria tenella,the number of OTUs and the Chao1 index in the model group decreased extremely significantly,and Shannon index in the model group decreased significantly,the Simpson index increased significantly.The composition of the bacteria group:at the phylum level,the abundance of Proteobacteria in the model group was increased extremely significantly,while that of Firmicutes was reduced extremely significantly.At the genus level,the predominant bacteria in the normal group were Bacteroides,Ruminococcaceae-UCG014,and Parabacteroides;in the model group,the relative abundance of Ruminococcaceae_uncultured,Tyzzerella and Escherichia-Shigella increased extremely significantly.Eimeria tenella disrupted the integrity of the cecal microbiota and promotes the establishment and growth of potentially pathogenic bacteria,especially the growth of Escherichia-Shigella.