Growth of the Eurasian perch (Perca fluviatilis L.) reared in floating cages and in water recirculated system: first results

For 8 weeks, perch (22–25 g) were reared in a water recirculated system (WRS) and in floating cages (FC), and fed with an artificial food for 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 indices (3.0 vs 4.1) and lower growth variability. WRS appeared more adapted to raise perch than FC. Nevertheless, sexual growth dimorphism in favour 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.