Effects of dietary tributyrin on growth performance, body composition, serum biochemical indexes and lipid metabolism-related genes expression of juvenile large yellow croaker (Larimichthys crocea) fed with high level soybean oil diets

A 10-week feed trial was conducted to investigate the effects of tributyrin (TB) supplementation on growth performance, body composition, serum biochemical indexes and lipid metabolism-related genes expression of juvenile large yellow croaker (Larimichthys crocea) fed diets containing high level of soybean oil. In the negative control group, 80 g/kg fish oil was used as the only lipid source (FO group), while in the positive control group, 20 g/kg fish oil and 60 g/kg soybean oil were used as the lipid source (FS group). Based on the positive control diet, grade levels of 1, 2, 4 and 8 g/kg tributyrin were added, respectively. Results showed that compared with the negative control group, high level of dietary soybean oil significantly decreased the growth performance and increased the liver lipids deposition of juvenile large yellow croaker. Compared with the positive control group, supplementation of 2 g/kg tributyrin significantly increased the growth performance and reduced the liver triglycerides and serum cholesterol content of juvenile large yellow croaker. Supplementation of 4 g/kg tributyrin significantly decreased liver triglycerides and serum cholesterol and free fatty acids content of juvenile large yellow croaker. Moreover, supplementation of 2 and 4 g/kg tributyrin significantly decreased the expression of acc, srebp-1, and ppar gamma and significantly increased the expression of cpt1. Results of the present study indicated that moderate tributyrin supplementation in diet containing high level of soybean oil could promote growth performance and reduce liver fat accumulation and hyperlipidemia of cultured juvenile large yellow croaker, which could be due to the decrease in lipogenesis-related genes expression and the increase in lipid oxidation-related genes expression.