Effects of dietary sodium butyrate on growth, digestive enzymes, body composition and nutrient retention-related gene expression of juvenile yellow catfish (Pelteobagrus fulvidraco)

Abstract An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate (SB) on growth, digestive enzymes, body composition and nutrient retention-related gene expression of juvenile yellow catfish (Pelteobagrus fulvidraco). Five isonitrogenous and isolipidic diets (420 g/kg protein and 90 g/kg lipid) were formulated to contain 0 (control), 250, 500, 1,000 or 2,000 mg/kg SB. Triplicate groups of 40 fish (BW = 1.26 ± 0.01 g) per tank (300-L cylindrical fiberglass tanks) for each diet were fed to apparent satiation twice daily. Stomach, hepatopancreas and intestine samples were obtained for digestive enzymes activities analyses. A real-time quantitative PCR analysis was performed to determine the relative expression of target of rapamycin (TOR) and lipoprotein lipase (LPL) in the hepatopancreas and intestine. Fish fed the diets supplemented with SB at 500 and 1,000 mg/kg showed significantly higher specific growth rate and significantly lower feed conversion ratio compared to the control (P