Growth Performance and Feed Utilization of Russian Sturgeon Acipenser gueldenstaedtii Brandt Ratzeburg, 1833 in Grow-out Phase Cultured in the Black Sea

The aim of present study was to determine the growth performance of Russian sturgeon Acipenser gueldenstaedtii throughout 5 years and to investigate problems encountered in grow-out phase. Fish samples (2750.88±351.18 g, 80.18±6.49 cm mean±SD) were equally stocked into fiberglass tanks, three replicate per treatment and fed for 5 years. Gain of weight and length, Specific Growth Rate (SGR), Condition Factor (CF) and Feed Conversion Ratio (FCR) were determined. Our results indicated that mean final length and weight were 106.34±2.79 (cm) and 6651.16±3.16 (g). The mean condition factor (CF) at year 5 was 0.51. FCR values fluctuated and the highest value of food conversion rate (FCR) was determined in 4th year. During the rearing period of Russian sturgeon, SGR values decreased dramatically from 2.88 to 1.83. In conclusion, slow growth was determined in Russian sturgeon A. gueldenstaedtii. Therefore, there is need for extensive evaluation and comparison of data obtained from field studies and those obtained from laboratory studies.