Effects of butyrate glycerides supplementation in high soybean meal diet on growth performance, intestinal morphology and antioxidative status of juvenile black sea bream, Acanthopagrus schlegelii

This study aimed to investigate the effects of graded butyrate glyceride (BG) supplementation levels in high soybean meal diet on juvenile black sea bream. Three hundred and sixty fish were fed diets containing 199 g/kg fishmeal and 450 g/kg soybean meal, with increasing levels of BG at 0, 2, 4, 6, 8 or 16 g/kg for eight weeks. The growth performance of the fish increased with increasing dietary BG supplementation up to 6 g BG/kg, beyond which growth rate reduced significantly (p < .05). Dietary BG supplementation increased the intestinal protease activity, but had no significant (p > .05) effect on lipase and amylase activities. Fish fed the basal diet exhibited villus shortening with a decrease in the number of goblet cells and a reduction in absorptive and digestive epithelial surface, while fish fed >= 4 g BG/kg diets showed a well-integrated gut, with large absorptive and digestive epithelial surface. Dietary BG supplementation also improved antioxidative capacity by increasing superoxide dismutase and glutathione peroxidase activities while decreasing malondialdehyde content. The inclusion of BG in high soybean meal diets can improve growth performance, maintain healthy gut morphology and enhance antioxidative capacity of black sea bream.