Growth response of the freshwater prawn Macrobrachium malcolmsonii (juveniles) to isocaloric diets with variable protein levels.

A B S T R A C T Indoor culture of freshwater prawn is considered to be an alternative and sustainable approach in order to meet the market demand. Culture potential of freshwater prawn (Macrobrachium malcolmsonii) under laboratory conditions was determined by growth trials performed in glass aquaria. The dietary protein requirement of M. malcolmsonii juveniles was analyzed using rations based on fish meal and shrimp meal as the main sources of protein. Five protein levels T1 (30%), T2 (32.5%), T3 (35%), T4 (37.5%) and T5 (40%) were tested to assess the best growth. Overall maximum growth was observed in T3 while minimum growth was observed in T4. Significantly higher (p<0.05) average weight, % weight gain and SGR was observed in T2 and T3 diets as compared to T1, T4 and T5 diets. Feed conversion ratio was significantly lower (p<0.05) in T2 and T3and but significantly higher (p˂0.05) in T1, T4 and T5. Water quality parameters like dissolved oxygen, ammonia, nitrate, and nitrite were recorded to be within the permissible limits while temperature, pH, alkalinity and hardness were found to be slightly higher than the permissible limits.