anoushiravan jafarzadeh

The aim of the present study was to evaluate dissolved oxygen concentration on growth and muscle composition of great sturgeon, Huso huso, in two weight groups (initial weight 280.9±49.2 and 1217.9±138.1). Oxygen treatments including hypoxia (2-3 mg/l), normoxia (5-6 mg/l) and hyperoxia (9-10 mg/l) were prepared by adjusting inflowing water and utilizing equipments for providing hyperoxygenation (pure oxygen injection). Fish were acclimated to experimental tank for one week and each group were randomly distributed in 9 tanks (3 fish per tank in higher weight group and 6 fish per tank for lower one) for 8 weeks. There were significant differences between treatments for Wt, WG, BWI, FI and SGR in both groups and CF in higher weight group (P<0.05). Muscle composition analysis showed no significant differences among the treatments in lower weight group (P>0.05) but moisture and fat content showed significant differences between treatments in higher weight group (P<0.05). Results indicated that high oxygen level has a direct effect on growth performance of great sturgeon and hence the use of a high oxygen level is recommended for the culture of great sturgeon.