Correlation of microbiota in the gut of fish species and water.

To analyze the intestinal microbiota diversity of several important economic fishes in the Loudi area and its correlation with the microbiota of water environment, the high-throughput sequencing based on the bacteria 16S rRNA was used to analyze the intestinal microbiota diversity in fish intestines and water. The results revealed that half of the OTUs in the water sample could be detected in the fish intestine, the proportion of shared OTUs in the intestines of and water samples was only 22%, and the unique OTU in the LC group was relatively the highest in the fish intestinal group. It can be seen from the analysis in NMDS analysis, the distance between group and water group is relatively farthest. has the highest microbiota richness and diversity ( < 0.05), while the water samples have the lowest microbiota richness ( < 0.05). Firmicutes, and are the prevalent taxonomic unit in the and groups, is the prevalent genera in the group, Proteobacteria and Cyanobacteria have a high relative abundance ratio in the group, and the prevalent taxonomic unit in the water sample group are , Bacteroidetes and Actinobacteria. In conclusion, fish species have different prevalent microbiota. There are a strong correlation between fish intestinal microbiota and the water environment, and the fish with a weak correlation is . Results of this study will contribute to the prevention and treatment of fish diseases and the fish ecological culturing in Loudi area.