Response of gut microbiota to feed-borne bacteria depends on fish growth rate: a snapshot survey of farmed juvenile Takifugu obscurus

Understanding the ecological processes in controlling the assemblage of gut microbiota becomes an essential prerequisite for a more sustainable aquaculture. Here we used 16S rRNA amplicon sequencing to characterize the hindgut microbiota from cultured obscure puffer Takifugu obscurus. The gut microbiota is featured with lower alpha-diversity, greater beta-dispersion and higher average 16S rRNA copy numbers comparing to water and sediment, but far less so to feed. SourceTracker predicted a notable source signature from feed in gut microbiota. Furthermore, effect of varying degrees of feed-associated bacteria on compositional, functional and phylogenetic diversity of gut microbiota were revealed. Coincidently, considerable increase of species richness and feed source proportions both were observed in slow growth fugu, implying a reduced stability in gut microbiota upon bacterial disturbance from feed. Moreover, quantitative ecological analytic framework was applied and the ecological processes underlying such community shift were determined. In the context of lower degree of feed disturbance, homogeneous selection and dispersal limitation largely contribute to the community stability and partial variations among hosts. Whilst wit...Continue Reading