INFLUENCE OF Aspergillus oryzae FERMENTED SOYBEAN MEAL ON PLASMA CHOLESTEROL AND BILE ACID LEVELS IN HYBRID TILAPIA AND POMPANO FISH

DOI: 10.18173/2354-1059.2020-0059

Tóm tắt

Fermentation has been suggested as an economical and effective method to eliminate anti-nutritional factors and improve the nutritional value of Defatted soybean meal (SBM). The present study aimed to examine the effects of Aspergillus oryzae fermented SBM (FSBM) on plasma cholesterol and bile acid levels in hybrid tilapia and pompano. Two isonitrogenous and isoenergetic experimental diets for each fish species were formulated with SBM and FSBM as main ingredients. The diets were denoted as SBMD (SBM-based diet) and FSBMD (FSBM-based diet). Thirty juvenile hybrid tilapia (initial body weight 55 g) and eighteen juvenile pompanos (initial body weight 61 g) were allocated to each of the 4 concrete tanks (1500-L holding capacity) and each of the 4 circular polyvinyl chloride tanks (500-L holding capacity), respectively, resulting in two replicate tanks per dietary treatment for each fish species. For 4 weeks, the fish were handfed the experimental diets to apparent satiation twice daily. The results showed that feeding FSBMD tended to increase plasma total cholesterol level, gallbladdersomatic index, anterior intestinal total bile acid level, and posterior\anterior intestinal total bile acid reduction rate compared to SBMD in both hybrid tilapia and pompano. The differences in these parameters between FSBMD and SBMD dietary groups were significant in hybrid tilapia (P < 0.05), while no significant differences were found between pompano fed FSBMD and SBMD. These results indicated that fermentation of SBM with A. oryzae could effectively improve physiological conditions of hybrid tilapia fed soybean proteinbased diet and suggested that inclusion of A. oryzae FSBM might enhance growth and feed performances of the fish.