Effects of dietary lipase supplementation on digestive enzyme activity and growth metrics of juvenile gilthead seabream (Sparus aurata L.)

This study investigated the effects of exogenous lipase supplementation on the growth performance, digestive enzyme activity and body chemical composition of Sparus aurata L. A total of 840 Sparus aurata (7.72 ± 0.05 g) were fed eight diets for 60 days. Diets were coded Group 1: Control 1 (G1–14% Lipid); Group 2: Control 2 (G2–22% Lipid); Group 3: 14% Lipid + 0.5 g lipase (G3– 0.5 g/kg); Group 4: 14% lipid + 1.0 g lipase (G4–1 g/kg); Group 5: 14% Lipid + 1.5 g lipase (G5–1.5 g/kg); Group 6: 22% lipid + 0.5 g lipase (G6–0.5 g/kg); Group 7: 22% Lipid + 1.0 g lipase (G7—1 g/kg) and Group 8: 22% Lipid + 1.5 g lipase (G8–1.5 g/kg). There were 8 dietary treatments that included a protein and lipid diet containing (14% and 22%), crude protein (50%) and supplemented with graded levels of exogenous lipase supplementation activity at 0.5, 1, 1.5 and 2 g/kg diet. As a result of the study, G3 group was better in the final weight (64.42 ± 1.06 g), the specific growth rate (3.55 ± 0.01) and the feed conversion rate (1.20 ± 0.18) compared to other groups (P <0.05). Protease, trypsin and alkaline phosphatase activity support growth and their activity increased during the trial. As regards amylase, lipase and aminopeptidase, a decrease in their activity was detected during the research.