“…The physiological state can include the health status of the aquatic organisms, their feeding status, and age. Studies on the health status of aquatic organisms have commonly detected differences in sex and body weight (Li, Yan, Einar, & Wu, ) and in feeds (Akter, Sutriana, Talpur, & Hashim, ; Giannenas, Karamaligas, Margaroni, & Pappas, ; Hao, Wu, Jakovlić, & Zou, ) and feeding methods (Rungrassamee, Klanchui, Maibunkaew, & Chaiyapechara, ; Tzeng, Pao, Chen, & Weng, ; Wang, Zhang, Li, & Lin, ). The differences in the gut microbiota at different ages and the exploration of the core bacteria have been studied frequently for human and model organism intestinal microbes; however, relatively little is known regarding gut bacteria in aquatic organisms.…”