Effects of different dietary of protein and lipid levels on the growth of freshwater prawns (Macrobrachium carcinus) broodstock

Objective. Evaluate the effects of varying dietary protein and lipid levels on the growth and body composition of adult freshwater prawns, Macrobrachium carcinus (Linnaeus 1758), in a recirculation system for 11 weeks (77 days). Materials and methods. The experimental treatments were assigned in triplicate. Six test diets were formulated with three different protein levels (35, 40 and 45%) and two lipid levels (8 and 13%). Results. The highest survival rate, growth indices and feed utilization were observed for M. carcinus adults fed protein:lipid diets of 35:13, 40:13 and 45:13, and the lowest values for these parameters were recorded for prawns fed diets with the lowest lipid levels; the differences in these parameters between these types of diets were significant (p<0.05). A non-significant tendency for an increased percentage of protein in the body with an increased dietary protein level was observed. The percentage of lipids decreased with an increasing dietary protein level, and no definite trends in ash content were found. Conclusions. The results suggest that a diet with 35% dietary crude protein and 13% lipids enhances the growth and body composition of adult M. carcinus.