OPTIMAL DIETARY-PROTEIN LEVEL OF PENAEUS-MONODON REARED IN SEAWATER AND BRACKISHWATER

The study was aimed at determining the optimal protein level for P. monodon reared in seawater and in brackish water. Six isoenergetic purified diets were prepared containing 32-52% protein level in 4% increments. These diets were fed at 8% of the body weight/day at two different salinity levels (16 ppt and 32 ppt) for 8 weeks. Results from this study indicated that weight gain and protein retention of shrimp were proportional to the protein content of the diet up to incorporation rate of 44% and 40% crude protein when shrimp were reared in 16 ppt and 32 ppt salinity, respectively. Beyond this level, no significant (p > 0.05) differences in weight gain and protein retention were found. Protein digestibility of each diet was identical regardless of the protein content in the diet. These results suggest that the optimal dietary protein level for P. monodon is about 44% in brackish (16 ppt) water and 40% in seawater (32 ppt).