Growth and survival of Cryphiops caementarius in coculture with Oreochromis niloticus at different densities

Objective. To evaluate the growth and survival of Cryphiops caementarius in coculture with Oreochromis niloticus at different densities. Materials and methods. Male prawns (5.86 cm and 7.65 g) and reverse tilapia fingerlings (5.65 cm and 2.61 g) were used. Nine aquariums (55 L) were used. Six containers were installed in each aquarium, where one prawn was stocked per container (32 prawn/m²), and in the remaining water, tilapia was stocked at densities of 100, 200 and 300 fish/m³. Balanced feed was used. The daily ration for prawns was 6% and for tilapia, it was 5% of the total biomass. The experiment lasted 90 days. Results. In prawns, the length (6.46 cm), weight (9.37 g), percentage gains in length (10.01% at 10.45%) weight (19.24% a 25.41%), and survival (88.89% to 94.44%) were similar (p<0.05) between treatments. The effect of molting death syndrome is discussed. In tilapia, the length (9.25 cm), weight (12.90 g), absolute growth rate (0.040 cm/day; 0.114 g/day), specific growth rate (0.55% length/day; 1.759% weight/day) and percentage gain (64.21%; 389.48%) were greater (p<0.05) at 100 and 200 fish/m³. Tilapia survival was similar (86.11%) between treatments. Conclusions. Prawn growth and survival were affected by molt death syndrome but not by the presence of tilapia in the system. In contrast, greater growth of tilapia was obtained with 100 fish/m³, although survival was similar between treatments.