高亚硝酸盐环境下不同生长速率凡纳滨对虾肠道微生物多样性研究

Growth variance and intestinal microbial diversity of Litopenaeus vannamei raised in high-nitrite environment

摘要:

【目的】高亚硝酸盐环境中饲养的凡纳滨对虾(Litopenaeus vannamei)，在养殖结束时其生长速率和体重往往差异较大。本研究旨在探讨在高亚硝酸盐环境下饲养的对虾生长速率与肠道菌群结构和功能的相关性。【方法】本研究通过收集高亚硝酸盐条件下快速生长对虾(rapidly growing, RG)、正常生长对虾(normally growing, NG)和缓慢生长对虾(slowly growing, SG)的肠道和海水样品，通过16S rRNA基因测序、线性判别分析[line discriminant analysis (LDA) effect size, LEfSe]等进行分析。【结果】发现SG的细菌群落多样性与RG和NG不同。主坐标分析(principal coordinate analysis, PCoA)分析表明，NG的群落组成与RG比SG更相似。通过LEfSe差异分析发现，RG中火色杆菌科(Flammeovirgaceae)、黄杆菌科(Flavobacteraceae)和浮酶菌科(Planctomycetaceae)的丰度较高，而SG中脱硫弧菌科(Desulfovibrionaceae)、希瓦氏菌科(Shewanellaceae)和弧菌科(Vibrionaceae)的丰度显著增加。【结论】本研究发现，在高亚硝酸盐环境下，肠道微生物群落的氮代谢能力是造成对虾不同生长速度的原因。该研究将为虾的工业化养殖提供指导。

Abstract:

[Objective] Pacific white shrimp (Litopenaeus vannamei) raised in high-nitrite environment tend to have different growth rates and body weights between individuals at the end of the culture period. This study aims to investigate the association between growth variance with intestinal microbiota structure of shrimps raised in a high-nitrite environment. [Methods] Intestinal contents and seawater samples were collected from rapidly growing, normally growing, and slowly growing shrimps raised in a high-nitrite pond for 16S rRNA gene sequencing and linear discriminant analysis effect size (LEfSe). [Results] The intestinal microbial diversity of the slowly growing shrimps was different from that of rapidly and normally growing shrimps. The principal coordinate analysis showed that the intestinal microbiota structure of the normally growing shrimps was more similar to that of the rapidly growing shrimps than to that of the slowly growing shrimps. The results of LEfSe revealed that Flammeovirgaceae, Flavobacteriaceae, and Planctomycetaceae had high abundance in the shrimps with rapid growth, while Desulfovibrionaceae, Shewanellaceae, and Vibrionaceae were significantly enriched in the shrimps with slow growth. [Conclusion] The difference in nitrogen metabolism capacity of intestinal microorganisms leads to the growth variance among shrimps in the high-nitrite environment. The findings provide new knowledge for the industrial farming of shrimps.