Preliminary study of diets supplemented with chitosan for white snook (Centropomus viridis) juveniles: effect on growth, survival, and nutritional efficiency

Due to its beneficial biological properties, chitosan extracted from crustacean byproducts emerges as a viable strategy to mitigate the anti-nutritional factors in vegetable-based diets for juvenile white snook (Centropomus viridis). The growth, survival, and nutritional efficiency of juvenile white snook-fed diets containing chitosan were evaluated. Chitosan was extracted chemically and enzymatically from shrimp byproducts (exoskeletons and heads). It was then included in a soybean meal-based diet (48% protein and 19% kJ g-1 gross energy) at 0, 0.5, and 1.0% chitosan levels (D-Control, CHI-0.5%, and CHI-1.0%). Juvenile snook (initial weight: 44.5 ± 4.2 g) were randomly distributed into 300 L tanks and fed the experimental diets three times daily for 45 days. Fish fed the CHI-0.5% and CHI-1.0% diets were significantly (P < 0.05) higher in growth rates than the D-Control diet. No significant differences in survival were observed. The FCR of the CHI-0.5% and CHI-1.0% diets were lower when compared to the D-Control (P < 0.05). The results suggest the utilization of chitosan in diets with high soybean meal content for snook to obtain better growth and survival.