prawn gut microbiota
Gut microorganisms play important roles in host health, but their roles in aquatic animal hosts are not well understood. The oriental river prawn, Macrobrachium nipponense, is one such example. We aimed to identify the shift in gut microbiota caused by microsporidium Potaspora macrobrachium, an emerging disease in prawn aquaculture, and so exert some con-trol over microsporidian pathogenesis. In the present study, histopathology revealed substantial microsporidian infections in infected prawns. We also investigated the changes in composition and structure of the prawn gut microbiome after microsporidian infection, utilizing a 16S rRNA method and Illumina MiSeq sequencing technology. Variation in bacterial community structure suggested that microsporidian infection had a major impact on the gut microbiome, as unique clusters were mostly determined by infection status. Across all samples, four major phyla were identified: Proteobacteria (86.4%), Bacteroidota (6.89%), Firmicutes (3.41%), and Actinobac-teriota (1.69%), each having a distinct abundance and variation pattern. Rikenellaceae, Pseu-domonas oryzihabitans, Anaerovibrio, Gracilibacteria, Hungatella, Bacteroides fragilis, Bacil-lus cereus, Chitinophagaceae, and Psychrobacter are examples of indicator taxa that clearly distinguish between prawn health states. The variations in bacterial community functions be-tween healthy and diseased prawns were primarily evident in metabolism (carbohydrate metab-olism, amino acid metabolism, and cofactor and vitamin metabolism), implying that disease al-tered the metabolic mode of gut microbiota.