The role of intestinal microbiota and their metabolites in governing the health and growth of hosts, especially in fish, remains a subject of extensive research, particularly in the realm of multi-omics within animal or fish nutrition. In a study detailed in the March 2023 edition of the Environmental Research journal titled "Integrative analysis of microbiome and metabolome reveals the linkage between gut microbiota and carp growth (DOI: 10.1016/j.envres.2022.115133)," researchers delved into the intricate connection between the gut microbiota and the growth disparities observed in fast-growing (FG group) and slow-growing (SG group) carp.
Examination of the 16S rRNA gene sequencing in the carp groups exposed noteworthy differences in their gut microbiota composition. Alpha diversity analysis underscored higher richness and diversity in the SG group compared to the FG group, while PCoA analysis distinctly segregated the samples from these two groups. Further analysis pinpointed the significance of the Cyanobacteria phylum (LDA > 4.8) in the SG group's microbiota and the Aeromonadaceae family (LDA > 3.6) in the FG group through LEfSe analysis.
The non-targeted LC-MS/MS metabolome analysis of intestinal metabolites in both group uncovered 191 differentially expressed metabolites, shedding light on pathways related to lipid metabolism, amino acid metabolism, and steroid biosynthesis through KEGG pathway analysis. The validation process connected metabolite variations to changes in intestinal bacteria, showcasing consistent predictions from PICRUSt2 regarding potential KEGG functions for the groups. This correlation emphasizes how distinct metabolic gene pools in different gut microbiota may contribute to variations in intestinal metabolites.
In essence, the findings suggest that the composition of the intestinal microbiota, notably cyanobacteria, significantly influences carp growth performance. Their unique metabolic functions produce specific metabolites that either boost or hinder nutrient absorption and energy acquisition by the host. This underscores the pivotal role of a healthy gut microbiota and its impact on fish growth, thereby setting the stage for future advancements in microbiome technologies within fisheries and aquaculture.