Effects of Stocking Density on the Growth Performance, Physiological Parameters and Antioxidant Status of Juvenile Common Carp (Cyprinus carpio L.) Reared in the Cage system

Stocking density is one of the most important factors influencing growth performance, health status and welfare of fish in aquaculture. This research was carried out to investigate the effect of different stocking densities on growth performance, feed utilization, survival rate, haematology, serum biochemistry and serum antioxidants enzyme responses in common carp juveniles (Cyprinus carpio L.) reared in outdoor cage culture. The fish were randomly stocked in four density groups; 7F fish/0.2m3 (Control group), 14F fish/0.2m3, 21F fish/0.2m3 and 28F fish/0.2m3 in 12 cylindrical cages (0.2m3) in concrete pond, with three cages in each density for 84 days. The results of the 14f density group significantly improved the FW, WG, SGR, FCR, FCE, PER, FI, PI, WBC, RBC, Hct, GSH and SOD activities. The 21F and 28F had significant impacts on FW, WG, SGR, FCR, FCE, PER, FI, PI, glucose, cortisol, ALT, AST, ALP, TG, MDA and GSH increased significantly with increasing stocking density. In contrast, the survival rate, TP, TG, HDL, GPx and SOD activities were significantly decreased. In general, the results demonstrated that the best stocking density is 14F fish/0.2m3 which provided a better growth performance and health status of C. carpio cultured in the cage in the concrete pond.