Correlation between gut microbial diversity and flatulence of silver pomfret ( Pampus argenteus ) during ontogenesis

Abstract

Gut microorganisms play an important role in host health and have susceptibility to diseases, undergoing a distinct transformation at early stages of development. This study aimed to determine the regulation of gut microorganism development from fertilized eggs to 150 DAH (days after hatching) and the differences between flatulent and healthy silver pomfret (Pampus argenteus). High-throughput sequencing was used to analyze the diversity and relative abundance of microorganisms. PICRUSt was used to predict functional alterations of dominant microorganisms. The results showed that from all 42 samples, a total of 3,746,895 reads were obtained, representing 6,081 operational taxonomic units (OTUs). Top 3 phyla were Proteobacteria, Firmicutes and Bacteroidetes. From 0 to 32 DAH, the relative abundance of Proteobacteria continuously increased and peaked at 94.99%. After that, the abundance of Proteobacteria decreased, but Bacteroidetes and Firmicutes increased instead. Alpha diversity is the lowest at 32 DAH, the difference is significant compared with others, p < .05. Comparing flatulent fish with healthy fish, the former has more specific OTUs, higher diversity and abundance. There were four genera Ethanoligenens, Methanobacterium, Caproiciproducens and Leptolinea that only obtained from the flatulent samples, but almost none in the healthy samples. All of these four genera are directly or indirectly involved in gas metabolism. This study enriched the basic research of silver pomfret, for the first time, focused on flatulent individuals which would provide a theoretical basis for the subsequent breeding.