Performance of juveniles of the fat snook Centropomus parallelus at different comercial diets and feeding frequencies

Abstract

The effect of two diets (CAM: for penaeid shrimp, 45% Crude Protein - CP; PEIXE: for freshwater carnivorous fish, 40% CP) and two feeding frequencies (one and two meals per day) was evaluated on the growth of fat snook, Centropomus parallelus, juveniles of 138 Days After Hatching (DAH) (weight 4.1 ± 0.1 g, total length 7.8 ± 0.1 cm; mean ± standard error). Animals were stocked at 0.44 fish/L and feeding was done to apparent satiation for 73 days. Feeding frequencies did not affect weight (W), standard (SL) and total length (TL), specific-growth rate (SGR), weight gain (WG) and condition factor (K) (P>0.05). However, with the CAM diet, higher W, TL, SL and WG were obtained compared to the PEIXE diet. The SGR (1.3%/day) and K (1.8) were also superior. Although higher growth occurred within this diet, the feed conversion ratio was similar for both diets and feeding frequencies. In this way, probably the amount of feed necessary to attain the commercial size for fat snook would be the same for the diets tested. However, with the CAM diet, fat snook would achieve the commercial size faster due to the higher growth rate, reducing labor and facility costs by diminishing the cultivation time. Once the feeding frequencies tested did not affect growth performance of fat snook, it is recommended for this age, in well fed animals, to feed them once a day.