Effects of dietary sodium acetate on intestinal health of juvenile Trachinotus ovatus based on multi-omics approach

Short-chain fatty acids (SCFAs) have been widely applied in aquaculture. Previous studies mainly focused on phenotypic level involved in the trophic function of SCFAs. Integration of intestinal microbiota and lipidomic and transcriptomics responses could deepen our understanding of the underlying mechanism of SCFAs. This study was performed to investigate the influences of sodium acetate (SA) on intestinal health of juvenile golden pompano (Trachinotus ovatus). Two isonitrogenous and isolipidic diets, including the control (C) group and SA group were fed to juvenile golden pompano (average weight 8.68 ± 0.07 g) for 8 weeks. The results showed that dietary SA significantly increased the activities of intestinal chymotrypsin, lipase and α-amylase enzymes as well as intestinal villus number and intestinal wall thickness (P < 0.05), while intestinal pH significantly decreased (P < 0.05). SA supplement significantly increased levels of butyric acid, valcric acid and caproic acid (P < 0.05) and significantly decreased levels of acetic acid, propionic acid and isvalcric acid (P < 0.05). SA supplementation significantly promoted intestinal microbiota alpha diversity and regulated microbial community composition by increasing the abundances of putatively beneficial bacteria such as Turicibacter and Labrenzia (P < 0.05). Besides, SA supplementation changed the lipid profile of intestinal metabolites through remodeling the abundances of Glycerolipids, Glycerophospholipids and Sphingolipids. SA supplementation promoted the upregulation of differential genes in “immune system process”, “transcription regulator activity”, “PI3K-Akt signaling pathway”, “Endocytosis”, “AMPK signaling pathway” and “Tight junction” (P < 0.05). This study provides a further insight into view for the benefit of SA on gut health of golden pompano.