Difference analysis of gut microbiota of golden pompano Trachinotus ovatus (Linnaeus, 1758) with the unsynchronized growth by feeding fermented soybean meal

Golden pompano (Trachinotus ovatus) is a commercially important marine fish and is widely cultured in the coastal area of South China. We explored the distribution difference of intestinal microflora with the same growth condition and the difference of gut microflora with different growth rates fed with fermented soybean meal (FSM) and fish meal (FM) primary protein source. After 8 weeks of the breeding experiment, select significant growth fish (Zcd, 156.04 +/- 1.04 g) average growth fish (Zc, 120.01 +/- 1.05 g) stagnant growth fish (Zcx, 98.03 +/- 1.08 g) in FSM and select average growth fish (Dc, 158.03 +/- 1.02 g) in FM. Sequencing results show that a total of 86303 sequences had been obtained in the intestine of Trachinotus ovatus. The number of OTUs that can be annotated to the database was 2315 (98.97%). At the phylum level, Proteobacteria, Tenericutes, Spirochaetes and Firmicutes were the predominant phyla. Alpha diversity and beta diversity analyses show that gut microbes' richness and diversity in the Dc group were the highest. The diversity of gut microbiota in the FSM: Zc > Zcd >Zcx. At the genus classification level, the differences between FM and FSM were mainly in Gueglia, Grimontia, Klebsiella, Alistipes, Staphylococcus, and Parasutterella (p <0.05). Alistipes and Staphylococcus were the different genera between Dc and Zcd (p <0.05). We found significant differences in the relative abundance of Ruegeria between the Zc and Zcd groups. Also, significant differences were found in the distribution of Brevinema, Ruegeria, Unidentified-Lachnospiraceae, Blautia, and Bacteroides between Zc and Zcx groups. The results showed that fermented soybean meal had an essential effect on gut microflora of T. ovatus with the unsynchronized growth.