Effect of Dietary Protein and Lipid Ratios on Zootechnical Performance and Body Composition of African Native Freshwater Prawn Macrobrachium macrobrachion (Herklots, 1851) Juveniles

Abstract

Determination of protein and lipid requirements is crucial in prawn species aquaculture. The present study investigated the impact of six diets with different protein and lipid levels (T1, 30/08; T2, 30/12; T3, 35/08; T4, 35/12; T5, 40/08; and T6, 40/12), in triplicate, on the zootechnical performance and body composition of juvenile Macrobrachium macrobrachion over 56 days. These protein and lipid levels were chosen based on the requirements of other freshwater prawn species. The stocking density was one individual per liter. Results show that prawn survival was lower in T6 (with 40% protein and 8% lipid) compared to all others. The treatment T3 (35% protein and 8% lipid) shows higher survival (with 40.0 ± 24.0%) but not significantly different from other diets. The specific growth rate obtained in the present study was not different between diets. Negative values were recorded for treatments T2, T3, and T4 (30%, 35%, and 35% proteins and 12%, 8%, and 12% lipids, respectively) and positive values for treatments T1, T5, and T6 (30%, 40%, and 40% proteins and 8%, 8%, and 12% lipids, respectively). The protein efficiency coefficient (PEC) and the lipid efficiency coefficient (LEC) did not differ between treatments; however, there was a trend for these coefficients to be lower in T4, T5, and T6 (35%, 40%, and 40% proteins and 12%, 8%, and 12% lipids, respectively) compared with the other diets. The highest protein efficiency rates were recorded with the T3 and T4 treatments (35% proteins and 8% and 12% lipids, respectively), while the best lipid level was obtained with T4 (35% proteins and 12% lipids). According to dose–response models, the optimal protein/lipid ratio requirements for M. macrobrachion juveniles can be estimated at 35/8. This study is the first to provide relevant information on the nutritional needs of juveniles of African native freshwater prawn M. Macrobrachion. Further research is needed to optimize nutritional requirements at early stages of development.