El-Sherif, M. (2009). EFFECTS OF PHOTOPERIODS ON THE GROWTH PERFORMANCE, FEED INTAKE AND FEED EFFICIENCY OF GILTHEAD SEA BREAM (Sparus aurata) JUVENILES. Journal of Animal and Poultry Production, 34(5), 4507-4515. doi: 10.21608/jappmu.2009.116990
M. S. El-Sherif. "EFFECTS OF PHOTOPERIODS ON THE GROWTH PERFORMANCE, FEED INTAKE AND FEED EFFICIENCY OF GILTHEAD SEA BREAM (Sparus aurata) JUVENILES". Journal of Animal and Poultry Production, 34, 5, 2009, 4507-4515. doi: 10.21608/jappmu.2009.116990
El-Sherif, M. (2009). 'EFFECTS OF PHOTOPERIODS ON THE GROWTH PERFORMANCE, FEED INTAKE AND FEED EFFICIENCY OF GILTHEAD SEA BREAM (Sparus aurata) JUVENILES', Journal of Animal and Poultry Production, 34(5), pp. 4507-4515. doi: 10.21608/jappmu.2009.116990
El-Sherif, M. EFFECTS OF PHOTOPERIODS ON THE GROWTH PERFORMANCE, FEED INTAKE AND FEED EFFICIENCY OF GILTHEAD SEA BREAM (Sparus aurata) JUVENILES. Journal of Animal and Poultry Production, 2009; 34(5): 4507-4515. doi: 10.21608/jappmu.2009.116990
EFFECTS OF PHOTOPERIODS ON THE GROWTH PERFORMANCE, FEED INTAKE AND FEED EFFICIENCY OF GILTHEAD SEA BREAM (Sparus aurata) JUVENILES
Animal Prod. and Fish Reso. Dept., Fac. of Agric., Suez Canal Univ., Ismailia, Egypt
Abstract
In this study, gilthead sea bream (Sparus aurata) juveniles weighting 16.3 ± 0.3 g were reared at a density of 40 fish per 200-L fiberglass tanks for 42 days. The experimental treatments were four photoperiods (6L:6D, 12L:12D, 16L:8D and 24L:0D) with constant light intensity 1500 lx on the water surface. Growth performance, Feed intake, feed conversion efficiency (FCE) and survival rate were investigated. The fish were fed twice daily using a commercial diet containing 46% crude protein at a rate of 2.5 - 3% of body weight/day. The growth measurements were recorded at 15-day intervals during the experimental period. Significantly higher weight gain and specific growth rates were observed in fish exposed to a 24L:0D photoperiod followed by 16L:8D, 6L:6D and 12L:12D photoperiods (P < 0.05), respectively. Feed intake was significantly higher in fish exposed to 24L:0D followed by 16L:6D, 6L:8D and 12L:12D photoperiods (P < 0.05), respectively. The FCE was significantly higher for fish exposed to 24L:0D and 16L:8D than those exposed to 6L:6D and 12L:12D. The carcass contents of all treatments were unaffected (P > 0.05) by varying the photoperiod. These results demonstrated that growth performance, feed utilization and survival rate of gilthead sea bream (Sparus aurata) juveniles weighting 16.3 ±0.3 g can be stimulated significantly by using either a long (16L:8D) or continuous (24L:0D) photoperiod which could be carried out for rearing marine fish juveniles.