The Effect of Gut Microbiota and Probiotics on Metabolism in Fish and Shrimp

SIMPLE SUMMARY: The gastrointestinal microbiota and probiotic supplementations play a vital role in fish and shellfish health. Therefore, it is important to increase our knowledge and experience on their effect on lipid-, carbohydrate- and protein metabolism. Even though some information is available, further studies are needed to achieve sustainable aquaculture. ABSTRACT: The present paper presents an overview of the effects of gut microbiota and probiotics on lipid-, carbohydrate-, protein- and amino acid metabolism in fish and shrimp. In probiotic fish studies, the zebrafish (Danio rerio) model is the most frequently used, and probiotic administration reveals the effect on glucose homeostasis, anti-lipidemic effects and increasing short-chain fatty acids, and increased expressions of genes related to carbohydrate metabolism and innate immunity, along with down-regulation of oxidative stress-related genes. Further, improved length of the intestinal villi and expression of nutrient transporters in fish owing to probiotics exposure have been documented. The present review will present an appraisal of the effect of intestinal microbiota and probiotic administration on the metabolism of nutrients and metabolites related to stress and immunity in diverse fish- and shrimp species. Furthermore, to give the reader satisfactory information on the topics discussed, some information from endothermic animals is also presented.