TEMPORAL SUCCESSION, KEYSTONE MICROBIOTA IDENTIFICATION, AND CORRELATION ANALYSIS BETWEEN THE INTESTINAL MICROBIOTA OF JUVENILE <italic>NIBEA ALBIFLORA</italic> AND THE BACTERIAL COMMUNITY IN CULTURE WATER

To examine temporal patterns in the intestinal microbiota of juvenile Nibea albiflora, as well as their associations with rearing-water bacterial communities, intestinal contents and corresponding water samples were collected at 36, 46, 66, 86, and 106 days post-hatching. High-throughput 16S rRNA gene sequencing and bioinformatics analyses were used to profile community composition, structure, succession, core taxa, and their relationships with host growth and rearing water microbiota. Across all sampling points, the Chao1 index of intestinal microbiota was significantly lower, while the Shannon index was significantly higher, than those in the rearing water. In the intestine, Chao1 increased initially then stabilized, whereas Shannon declined; in rearing water, Chao1 decreased and then increased, while Shannon showed the opposite trend (PPP>0.05). Habitat-specificity analysis, random forest modeling, and Mantel tests identified key taxa associated with juvenile growth, and two potentially autochthonous probiotic strains were successfully isolated from the intestine. These findings characterize the temporal dynamics and functional taxa of the intestinal microbiota in juvenile N. albiflora and their relationship to rearing-water communities, providing a foundation for developing host-specific probiotics in this species.