EFFECT OF FEEDING RATE ON GROWTH PERFORMANCE OF A. stellatus (PALLAS, 1771) REARED IN A RECIRCULATING AQUACULTURE SYSTEM

Şt.-M. Petrea, Alina Mogodan, Ira-Adeline Simionov, V. Cristea

Abstract
   Recirculating aquaculture systems (RAS) represents the most suitable solution for rearing sturgeons in intensive conditions, situation which imposes the use of a proper technology, respectively feeding rate, for a certain fish development stage. The aim of present study is to evaluate the effect of feeding rate on growth performance of stellate sturgeon (330.55±44.27 g) reared in RAS conditions. Two feeding rates were tested (F1 - 1% BW, respectively F2 - 2% BW), in replicate Biomass measurements were made at the middle of the experimental period, in order to adjust the daily administrated feed quantity. The average specific growth rate indicates a superior fish production at F2 (1.15 %BW/day), compared to F1 (0.65 %BW/day) experimental variant. However, from the perspective of feeding strategy efficiency, the average food conversion ratio (FCR) indicates better values for F1 experimental variant (1.5 g feed/g biomass gain), compared to F2 (1.61 g feed/g biomass gain). The protein efficiency ratio (PER) registered higher values at F1 experimental variant (1.67), compared to F2 (1.53), revealing the ability of fish organism to utilize proteins, which positively affects growth rate. Therefore, as a conclusion, it can be stated that during the analyzed stellate sturgeon development stage a better cost efficiency is recorded when applying 1% BW feeding rate, although if production maximization is targeted, 2% BW feeding rate is recommended.

Key words: stellate sturgeon, RAS, feeding rate, FCR, PER, SGR