Effects of bile acids supplementation in soybean meal‐based diet on growth, cholesterol status, digestibility and moulting‐related gene expression in white shrimp Litopenaeus vannamei

Abstract

The study evaluated the effects of bile acids (BA) supplementation in soybean meal (SBM)-based diet on growth, cholesterol concentrations, nutrient digestibility and moulting-related gene expression in white shrimp, Litopenaeus vannamei. Control diet with 485.1 g kg-1 SBM was supplemented with 0, 1 and 2 g kg−1 of BA. Together with a reference diet with fish meal, total of four diets were fed to triplicate groups of shrimp (initial weight: 2.20 g) in a recirculation system for 56 days. Weight gain was higher (p < 0.05) in shrimp fed the reference diet than in shrimp fed the control diet. Shrimp fed the reference diet had higher whole body, hepatopancreatic and haemolymph cholesterol concentrations, dry matter, lipid and cholesterol digestibility than other treatments. The expression of the ecdysteroid receptor gene was the highest in shrimp fed the reference diet and the diet with 0.2% BA, followed by shrimp fed the diet with 1 g kg−1 BA and the lowest in shrimp fed the control diet. Shrimp fed the reference diet, and diets with 1 and 2 g kg−1 BA exhibited higher retinoic-X receptor, chitinase and chitin synthease gene expression than shrimp fed the control diet. Haemocyanin gene expression was higher in shrimp fed the reference diet than in shrimp fed the control diet. The results indicated that shrimp fed high SBM diet showed low body cholesterol concentrations, digestibility and moulting-related gene expression for white shrimp. Bile acids supplementation in SBM-based diet can improve moulting-related gene expressions but not for another physiological parameter.