Abstract

The host-associated microbiota plays a key role in various biological processes of the host, including immunity, nutrition, and growth. In the present study, we profiled microbiota from the skin-mucus and gut of Channa striata (murrel) during feeding and fasting conditions by utilizing the 16S ribosomal RNA gene sequencing approach. Comparison of the microbial profiles showed that the feeding and fasting rhythm can alter the bacterial diversity of skin-mucus and gut-associated bacterial communities. In brief, the skin-mucus and gut microbial communities of murrel consisted of 22 bacterial phyla and were mainly dominated by Actinobacteria (66.07–87.78%) and Proteobacteria (11.62–31.93%) under both feeding and fasting conditions. Arthrobacter and Rhodococcus, known for improving fish performance in terms of growth, immunity, and nutrition, were more abundant in both gut and skin-mucus. In addition, Vogesella, Brevundimonas, Sphingomonas, and Methylobacterium were present in the skin-mucus and gut samples. PICRUSt analysis revealed several metabolic pathways that were abundant in the fish-fed groups, such as carbohydrate metabolism, amino acid metabolism, membrane transport, energy metabolism, metabolism of cofactors and vitamins, and lipid metabolism. Feeding patterns can alter the diversity of the bacterial community, and the altered microbiota may have a differential role in the metabolic functions of fed and starved fish. This study provides baseline data on the microbial community associated with murrel and their possible contribution to host metabolism. However, these findings need to be further explored at the functional level to determine how dietary shifts regulate gut homeostasis and health.

Key words: Aquaculture; Channa striata; Metagenomics; Next-generation sequencing; Skin mucus and gut