| Growth and tissue superoxide dismutase (SOD), alkaline phosphatase (AKP), acid phosphatase (ACP) activities of Crucian carp (Carassius auratus) under two densities were compared from April to November in 2011. The results showed that growth and immune enzyme activities of Crucian carp in low density pond were lower than those in high density pond on April 7th, after higher than those in high density pond. The optimal growth period for Crucian carp was from July to Septemper. The results indicated that low breeding density would affect growth and immunity at initial breeding stage, while high breeding density resulted in bad growth and low immunity in the later breeding period. |
