Diet overwhelms host growth in governing the ecological succession of gut microbiota in golden pompano (Trachinotus ovatus)

The assembly and succession of the gut microbiota are important events in animal growth and have a significant impact on the productivity of aquaculture organisms, which can be influenced by the environment, growth stages, and dietary changes. However, little is known about how the growth of aquaculture organisms and dietary differences during growth affect the assembly of the gut microbiota. In this study, we fed golden pompano (Trachinotus ovatus) a regular diet and a high-fat, high-protein diet, respectively. We then used bacterial 16 S rRNA gene sequencing to study the gut microbiota at different growth stages and under different dietary conditions. We found that the gut microbiota of T. ovatus changes in response to different dietary conditions. Moreover, this divergence does not change with the growth of the host. This suggests that dietary differences largely explained the gut microbiota succession, while growth stage had no significant influence on gut microbiota succession in T. ovatus from 30 to 120 dph. This study, which includes the effects of growth stage and diet, increases our understanding of how the gut microbiota of the T. ovatus assembles and colonizes and also provides new insights into the study of the gut microbiota of other aquaculture fish.