Effects of dietary tributyrin supplementation on the growth performance, serum biochemistry, antioxidant capability and intestinal morphology and structure of golden pompano ( Trachinotus ovatus )

Abstract

This study was conducted to investigate the effects of dietary supplementation with tributyrin (TB) on the growth, serum biochemistry, antioxidant capability and intestinal morphology and structure of golden pompano (Trachinotus ovatus). Golden pompano was fed a diet containing four levels of TB (0%, 0.1%, 0.2% and 0.4%) for 56 days. The results showed that compared with the group without TB supplementation (the control group), with the addition of 0.2% and 0.4% TB, the final body weight (FBW) and weight gain rate (WGR) were significantly upregulated (p < 0.05), the specific growth rate (SGR) and feed conversion ratio (FCR) were significantly upregulated and downregulated respectively, with 0.2% TB addition (p < 0.05). In addition, serum levels of alkaline phosphatase (AKP), total antioxidant capacity (T-AOC) and total superoxide dismutase (T-SOD) were significantly increased, whereas the levels of aspartate transaminase (AST) and alanine transaminase (ALT), malondialdehyde (MDA) were significantly decreased with the addition of 0.1%, 0.2% and 0.4% TB (p < 0.05). Glutathione peroxidase (GPx) was significantly increased with 0.2% TB (p < 0.05), and glutathione (GSH) was significantly increased with 0.2% and 0.4% TB (p < 0.05). In the liver, T-AOC, T-SOD, GPx and GSH were all significantly upregulated, whereas MDA was significantly downregulated by the addition of 0.1%, 0.2% and 0.4% TB (p < 0.05). Moreover, the villus height was significantly increased by the addition of 0.1%, 0.2% and 0.4% in the anterior and posterior intestine (p < 0.05), whereas the villus width was significantly increased by the addition TB level at 0.1% and 0.2% in the anterior intestine and significantly increased only in the posterior intestine with 0.2% TB (p < 0.05). These data suggest that dietary TB can improve serum biochemistry, antioxidant capability, intestinal morphology and structure of golden pompano. However, dietary TB supplementation did not alter the whole-body composition (crude protein, moisture, ash and crude lipid), total protein (TP), albumin (ALB), total cholesterol (T-CHO), high-density lipoprotein cholesterol (HDL-C), globulin (GLB), triglyceride (TRIG), low-density lipoprotein cholesterol (LDL-C) in the serum and catalase (CAT) in the serum and liver. Moreover, based on the growth performance (WGR) and antioxidant related (MDA) indices in the serum and liver, the appropriate supplementation level of TB in golden pompano was estimated to be 0.25%, 0.29% and 0.32% using quadratic regression analysis respectively.