Combined effect of cycled starvation and feeding frequency growth performance and feed intake of gilthead sea bream (Sparus aurata)

This study was composed of two experiments:Ist experiment was conducted to evaluate the combined effect of cycled starvation and feeding frequency on growth, body composition and feed utilization of juvenile gilthead sea bream. Triplicate groups of 324 juveniles (initial weights of 10.40 ± 0.07g) were stocked in 27 tanks (150 l) and reared in flow-through sea water. A factorial experiment (3x3) was designed employing a continuously fed control group (A) and two cycled starvation groups: 1 day starvation/3 days satiation (B), 1 day starvation/5 days satiation (C). The feeds were applied in three feeding frequencies for each group(2, 4 and 6 times a day) and the experiment lasted for 60 days. Throughout the study, growth, weight gain, feed utilization (as feed efficiency and daily feed intake), specific growth rate (SGR) values were measured every twelve days. Oxygen concentration in each tank was monitored and oxygen consumption was calculated before and after feeding for each group. Cycled starvation, feeding frequency and interaction of these factors significantly affected growth and feed utilization of juvenile gilthead sea bream. Growth and weight gain were affected only by starvation. No interaction was found between feeding frequency and cycled starvation. There were no significant differences between body lipid levels among the groups. Oxygen consumption increased significantly after the feeding and following the starvation day. Our findings suggest that 1 day starvation followed by 5 days satiation at a feeding frequency of 4 times a day is sufficient to get complete compensation for juvenile gilthead sea bream.In the 2nd experiment, we estimated gastric evacuation rate (GER) of juvenile gilthead sea bream (19.4 ± 2.23 g). Following an initial meal to satiation, fish were serially dissected at 1, 2, 3, 4, 5, 6, 12 and 24 h post-prandially. GER of gilthead sea bream fed a single meal proved to be similar (relative feed content = 46.157e0.0354x; r2= 0.8912), with approximately half the meal passed within 2.44 hour and whole meal cleared from the stomach within 24 hour.