Effect of dietary carbohydrates and lipids on growth in cachama (Piaractus brachypomus)

The effects of diets with three contents of carbohydrates and lipids were evaluated on the growing performance of cachama Piaractus brachypomus juveniles (initial weight 7.8 ± 0.49 g). The experiments were performed a 3 × 3 factorial design (200, 280 and 360 g of carbohydrates and 40, 80 and 120 g of lipids kg−1). Protein content was kept constant in 320 g kg−1 and digestible energy between 11.3 and 16.1 MJ kg−1. Simple effects and interaction of factors on growth performance varied significantly (P   0.05) were observed with the lipid levels. Results indicate that cachama utilizes carbohydrates as energy source more efficiently than lipids; likewise, lipid levels over 40 g kg−1 depress growth at any carbohydrates level.