Effect of photoperiod regime on the growth performance, survival, swim bladder inflation and vertebral anomalies of pikeperch (Sander lucioperca) larvae in recirculating aquaculture systems (RAS)

Abstract

ABSTRACTThe effect of photoperiod on the growth performance, survival rate, swim bladder inflation (SBI) and presence of vertebral anomalies was evaluated in pikeperch larvae reared under intensive production in a recirculating system (RAS). Three different photoperiods were tested from 1 to 30 days post hatch, 12:12 LD, 16:8 LD and 24:0 LD. Larvae were stocked with an initial density of 100 larvae per liter, light intensity of 100 lx and 16.0°C water temperature. The SGR among treatments ranged between 11.17 and 12.04% day−1. The highest survival rate (56.7 ± 2.4%) was found in 24:0 LD with a negative effect on the number of larvae with SBI. The highest presence of vertebral anomalies at 30 dph was found in 24:0 LD (40.8 ± 8.2%) compared to 12:12 LD (2.5 ± 1.4%) and 16:8 LD (1.7 ± 1.6%). These results suggest that constant light compromises culture of pikeperch larvae in RAS. A 16:8 LD photoperiod seems suitable for the growth performance, SBI and low vertebral anomalies at this life stage.