Microbiota characteristics in Sebastes schlegelii intestine in early life stages

The structure of intestinal microbiota of black rockfish Sebastes schlegelii in five early development stages were determined in high throughput sequencing with Illumina MiSeq PE300 system. The relationship between intestinal microbial community and the environmental (including culture water and feed) microbiota and the abundance variation trends of core microbiota were investigated, based on which the source of some core microbiota was analyzed in this study. The results show that Proteobacteria and Firmicutes are the most dominant phyla in guts. At the genus level, there are obvious differences between the artificial breeding fish and wild adults in the intestinal microflora structure. The compositions of dominant genera are similar, although the structure of intestinal microbiota gradually changes with the growth of larvae and juveniles. The core microbiota including Bacillus, Acinetobacter, Pseudomonas, Lactobacillus, Lactococcus, Glaciecola, Vibrio, Pseudoalteromonas, Acidovorax, and Aliivibrio were determined in the analysis of dominant and shared species. Compared with the water, the effect of feed microbiota on the structure of the gut microbial community is more obvious. Moreover, the trends of Bacillus, Acinetobacter, Pseudomonas, Lactobacillus, Lactococcus, and Glaciecola were opposite to Vibrio and Pseudoalteromonas in the gut. The correlation analysis suggested that Acidovorax, Glaciecola, Pseudomonas, Lactobacillus, and Acinetobacter might transited from mainly the parents and/or came from the fertilization process. The relative results may provide a theoretical reference for selecting the native probiotics, and supply the basic data for artificially regulating the intestinal microbiota with probiotic during early developmental stage of black rockfish.