GROWTH OF THE EURASIAN PERCH (PERCA-FLUVIATILIS L) REARED IN FLOATINGCAGES AND IN WATER RECIRCULATED SYSTEM - FIRST RESULTS

For 8 weeks, perch (22-25 g) were reared in a water recirculated syste m (WRS) and in floating cages (FC), and fed with an artificial food fo r trout. These two culture systems resulted in similar specific growth rates (1.1-1.4%/day). However, at 4% feeding rate, WRS ensured higher survival rates (90-100%) vs. FC (70-80%), better food conversion indi ces (3.0 vs 4.1) and lower growth variability. WRS appeared more adapt ed to raise perch than FC. Nevertheless, sexual growth dimorphism in f avour of females existed in WRS with restricted feeding rate (2% body weight per day). Likewise, this preliminary study suggested an effect of the rearing system on the perch body composition.