Structural Analysis and Functional Prediction of Gut Microbiota in Wild and Cultured Striped Knifejaw (Oplegnathus fasciatus)

Understanding the role of gut microbiota in fish health is crucial for optimizing aquaculture practices and ensuring sustainable fish populations. In this study, the diversity and compositional differences of intestinal microbiota were comparatively analyzed between wild and cultured striped knifejaw (Oplegnathus fasciatus Kroyer, 1845). Using high-throughput 16S rDNA sequencing and bioinformatics, an in-depth investigation of the gut microbiota in both populations was conducted. The results revealed that the number of intestinal bacterial sequences was significantly higher in the cultured population than in the wild population. The study included 16 individuals from the wild population and 38 individuals from the cultured population, with an average weight of 67.7 ± 12.4 g and 44.9 ± 16.8 g, respectively. Alpha diversity analysis indicated that intestinal microbiota species richness and diversity were both greater in the cultured O. fasciatus. Furthermore, significant differences were observed in the intestinal bacterial communities between the two populations, with Pseudomonadota, Verrucomicrobia, and Bacillota dominating in the cultured population, whereas Pseudomonadota overwhelmingly dominated in the wild population. Functional prediction analysis revealed differences between the intestinal microbiota in pathways related to genetic and environmental information processing, as well as metabolism. This study provides critical data for understanding the structure and function of intestinal microbial communities in O. fasciatus and offers a theoretical foundation for optimizing farming strategies to improve fish health and growth performance.