Comparative analysis of the bacterial community compositions of the shrimp intestine, surrounding water and sediment

Aims To reveal the relationship of the bacterial communities in shrimp intestine and surrounding environments. Methods and results We examined bacterial communities in the intestine of pacific white shrimp, Litopenaeus vannamei, the surrounding water and sediment by high-throughput sequencing analysis. Sequences were clustered into operational taxonomic units (OTUs) at 97% similarity levels, which ranged from 4956 to 5976 in each sample. All OTUs were affiliated with at least 64 phyla. The 10 most abundant phyla were Proteobacteria, Cyanobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Acidobacteria, Actinobacteria, Planctomycetes, Gemmatimonadetes and Verrucomicrobia. The relationship of bacterial communities in the intestine and the surroundings was also investigated. A total of 1395 OTUs shared in the three habitats, accounting for 80, 65 and 77% in the intestine, the surrounding water and sediment respectively. There were 352, 891, 833 unique OTUs in intestine, surrounding water and sediment. Welch's t-test analysis showed that the abundances of some taxa were significantly different between the shrimp intestine and surroundings. Unweighted pair-group method with arithmetic mean analysis revealed that there was a generally similar bacterial community composition in three environments. Conclusions These results showed that the bacterial compositions are mostly the same in shrimp intestine, water and sediment, but with different relative abundances of the bacterial communities. Significance and impact of the study This study provided valuable findings on the relationship of the bacterial communities in shrimp intestine, the surrounding water and sediment, which can expand our knowledge of the broad trend on bacterial community in shrimp cultural ecosystems.