添加不同益生菌对草鱼养殖水体菌群结构的影响

为评价添加不同益生菌对草鱼养殖水体菌群结构的影响，研究采用454焦磷酸测序技术分析其水体菌群结构。结果表明:添加益生菌后的处理组（枯草芽孢杆菌BS、光合细菌PSB和复合菌CB）其微生物多样性高于对照组（Control）。在门的水平，Control和CB样品中变形菌（Proteobacteria）为优势菌，PSB和BS中变形菌（Proteobacteria）和放线菌（Actinobacteria）所占比例差别不大。与Control相比，其他三组中拟杆菌（Bacteroidetes）和放线菌（Actinobacteria）都增加。对变形菌深入分析发现，在PSB，BS和 CB 样品中，-变形杆菌为优势菌，接下来是-变形杆菌纲、-变形杆菌纲和-变形杆菌纲。对拟杆菌分析发现，除对照外，其他样品中黄杆菌纲（Flavobacteria）为优势菌。在对照和处理组中，-变形杆菌、-变形杆菌、-变形杆菌和拟杆菌门在目的水平组成也有差异。以上结果表明，水体中添加益生菌能增加水体菌群多样性，改变菌群结构。  

COMPARATIVE ANALYSIS OF MICROBIAL COMMUNITY FROM GRASS CARP CULTURE WATER SUPPLEMENTATION WITH DIFFERENT PROBIOTICS

In this study, 454-pyrosequencing technology was employed to investigate the microbial community structure in grass carp culture water with or without different probiotics. The results showed that all three treatments remarkably increased the bacterial diversity compared to the control. In two samples (Control and CB), the dominant phylum was Proteobacteria. However, there was only moderate difference in the content of Proteobacteria and Actinobacteria between sample BS and PSB. Actinobacteria and Bacteroidetes in PSB, BS, and CB were more abundant than those in the control group. The detailed analysis of Proteobacteria showed that in PSB, BS and CB samples, the majority of Proteobacteria consisted of subdivision, followed by Betaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria; in the control sample, the dominant subtype was Gammaproteobacteria, followed by Betaproteobacteria, Alphaproteobacteria, and Deltaproteobacteria. For Bacteroidetes, Flavobacteria was the dominant subtype in treated samples but not in the control sample. At the order level we also oberseved a marked difference between the control and the treatment in terms of the composition of Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria and Bacteroidetes. The results indicated that the addition of different probiotics into water could increase the diversity and alter the structure of a microbial community.