Dietary Components Modulate the Gut Microbiota of Farmed Fish: Advances from the past Decade

Abstract

The composition of fish gut microbiota has direct implications for aquaculture productivity as alterations in these microbes profoundly affect several physiological functions of the fish. Nowadays, aquaculture feeding strategies increasingly shift from animal‐derived diets toward more sustainable plant‐based diets; understanding how the influence of a specific dietary component on fish gut microbiota has become increasingly important. Furthermore, the advancement of microbial genome sequencing technologies provides more comprehensive information on the effects of various dietary components on the gut microbiota of fish. Changes in these macronutrients and micronutrients can disrupt the eubiosis, gradually leading to dysbiosis by selectively enriching microbial guilds with distinct metabolic capacities, ultimately affecting the host‐microbial interaction, gut homeostasis, and overall fish health. Mostly, animal‐derived proteins and marine oils often favour the growth of bacteria that can metabolize proteins and lipids, whereas plant‐based proteins support the growth of bacteria that can ferment complex carbohydrates to produce beneficial metabolites, including short‐chain fatty acids. Feed additives are important to modulate the gut microbiota of fish via enhancing the abundance of beneficial bacterial species. Therefore, formulating aquafeeds by targeting on promoting the growth of beneficial gut microbiota and assessing the value of feed ingredients via considering the gut homeostasis indices seems useful. This review upgrades our knowledge on how dietary components interact and regulate the gut microbiota, ultimately influencing overall fish performance. Designing next‐generation aquafeeds and developing precision nutrition for the fish and their microbiota using advanced omics and artificial intelligence technologies to develop climate‐resilient fish farming is crucial.