Effects of dietary inclusion of lyophilized açai berries (Euterpe oleracea) on growth metrics, metabolic and antioxidant biomarkers, and skin color of juvenile tambaqui (Colossoma macropomum)

In this study, the effects of lyophilized Euterpe oleracea (LEO) as a dietary antioxidant additive were assessed on growth, skin coloration, bioactive muscle properties, metabolic parameters, and antioxidant status of tambaqui ( Colossoma macropomum ). Fish (initial body weight 0.92 ± 0.01 g) were fed five isoproteic (40% of crude protein) and isocaloric (20 kJ/g gross energy) diets (three replicates each) with graded LEO levels (6.3, 13, 25, 50, and 100 g per kg of diet), and a control group (0 g kg −1 LEO) at 10% of total biomass each day during 30 days. The experiment was conducted in a semistatic system (18 tanks of 200 L; N = 50 fish per tank). The results showed that the greatest final body length (7.92 ± 0.08 cm) was obtained in fish fed 50 g kg −1 LEO ( p