Effect of Cryphiops caementarius density in co-culture with Oreochromis niloticus on growth and survival in a recirculating aquaculture system

The aim of this study was to evaluate the effect of two stocking densities of the freshwater prawn Cryphiops caementarius co-cultured with the Nile tilapia Oreochromis niloticus on growth and survival in a recirculating aquaculture system (RAS). This shrimp/tilapia co-culture system consisted of four tilapia tanks (1 m3), with columns of 10 individual containers for prawn cultivation installed within each tank. Prawns were cultured in a columnar system at two densities of 10 and 20 shrimp/m3, with 100 juvenile tilapia/m3. Both species were fed with a balanced diet. The results indicated that prawn stocking density did not affect tilapia growth; however, tilapia growth was affected by a wide range of water temperatures (23 to 28 °C), but not by individual prawn culture container columns. Low prawn survival rates (25 and 37%) were associated with rising water temperatures above their optimal thermal zone, along with incomplete ecdysis syndrome, while those that performed chelipeds autotomy to survive showed slow growth rates. No tilapia mortality occurred. Further research into co-culture of shrimp with tilapia under temperature-controlled conditions is recommended.