不同生境草鱼肠道微生物组成和群落特征分析

Comparison of intestinal microbiome composition and community characteristics of grass carp from different habitats

【目的】分析不同生境来源的草鱼前肠、中肠和后肠的微生物组成和群落特征。【方法】利用16S rRNA高通量测序技术比较河流、湖泊、高密度池塘养殖与水库低密度养殖4种不同生境来源的草鱼其前、中、后肠的微生物组成和群落特征。【结果】Venn图、稀释性曲线和Alpha指数分析结果显示,前肠微生物群落多样性以养殖生境草鱼更高,而后肠微生物群落多样性以自然生境草鱼更高。不同生境草鱼前肠微生物组成和群落特征差异较大,自然生境的草鱼前肠微生物优势菌群都是不动杆菌属和贪铜菌属;高密度池塘养殖生境优势菌群是鲸杆菌属、希瓦氏菌属;低密度水库养殖生境的草鱼前肠优势菌群是链球菌属、消化链球菌属等。【结论】不同生境的环境因子不同,养殖方式不同,饵料不同,导致草鱼前肠微生物组成和群落特征的差异较大,该结果可为草鱼肠道微生物的研究提供基础数据。高密度养殖生境的草鱼存在潜在的感染风险,建议优化养殖模式以减少有害菌的产生。

[Objective]To analyze the microbiome composition and community characteristics of the foregut,midgut and hindgut of grass carp from different habitats.[Methods]The 16S rRNA high-throughput sequencing technology was applied to analyze the microbial composition and community characteristics of the foregut,midgut and hindgut of grass carp from four habitats,including river,lake,high-density pond culture and low-density reservoir culture.[Results]Venn diagram,Rarefaction Curve and Alpha index showed that microbial diversity of the foregut was higher in the cultured habitats than natural habitats(river and lake),whereas the diversity of the hindgut microbial community had the opposite trend.The microbial composition and community characteristics of the foregut of grass carp in different habitats varied greatly:the dominant microflora in the foregut was Acinetobacter and Cupriavidus in natural habitats,Cetobacterium and Shewanella in high-density culture pond,and Streptococcus and Peptostreptococcus in low-density culture reservoir.[Conclusion]The great differences in foregut microbial composition and community characteristics of grass carp were due to the difference of environmental factors,culture methods and diets.Our findings can provide basic data for the study of intestinal microorganisms of grass carp.There is a potential risk of infection for grass carp in high-density culture habitats,suggesting that the culture density should be controlled as much as possible in the culture of grass carp.