Bile Acid Supplementation with High-Fat Diet Impacts Fish Health and Gut Microbiota Function in Nile Tilapia (Oreochromis niloticus)

This project investigates how graded levels of dietary bile acid (BA) supplementation influence growth, physiological health, organ indices, and gut microbial diversity in Nile tilapia fed high-fat diets. Six experimental groups were assigned: a low-fat control, a high-fat control with no BA, and four high-fat diets with 0.05, 0.10, 0.15, and 0.20 g/kg BA. Fish were fed for 60 days, followed by assessments of growth metrics, hepatosomatic and viscera somatic indices, hematological and biochemical parameters, and 16S rRNA analysis of gut microbiota. Results show high-fat diets negatively affect tilapia growth and organ health, as indicated by increased organ indices and altered blood markers. Supplementation with BA especially at 0.10 to 0.15 g/kg improved growth rates, immune status, and gut microbial diversity, restored healthy organ sizes, and reduced adverse effects of high-fat feeding. This submission includes phenotypic, blood, organ, and microbiome sequencing data, supporting bile acid as a functional feed additive for sustainable fish farming.