Effects of light regimes on growth and survival of Penaeus semisulcatus

We investigated the possible effects of light regimes on growth and survival rate of juvenile shrimp Penaeus semisulcatus cultured in Bushehr Province, southern Iran. Five light regimes each with three replications were applied for 30 days. The treatments were 24/0, 18/6, 12/12, 6/18 and 0/24 hours of light and darkness. We found that the treatment 12/12 hours of light and darkness was better than 18/6 and significantly superior to other treatments (P<0.05). The lowest growth rate was seen in the treatment 24/0 (P<0.001). We did not find a significant difference in the survival rate of the shrimps cultured in the light and darkness treatments (P<0.05).