Effect of stocking density on growth performance of juvenile Amur Sturgeon (Acipenser schrenckii)

Experiments were carried out with juvenile Amur sturgeon (Acipenser schrenckii Brandt) including two size classes [small sized (SS) and large sized (LS)] to study the effect of stocking density on the growth when reared in indoor tanks. In the first trial (SS), the juveniles (8.70 +/- 0.90 cm total length) were reared at five relatively high initial stocking densities (120, 240, 360, 480, and 600 individuals m(-3)), whereas in the second trial (LS), the larger-sized juveniles (17.31 +/- 2.05 cm total length) were reared at five relatively lower stocking densities (50, 100, 150, 200, and 250 individuals m(-3)). Thus, the density differences refer to numbers rather than biomass. Each experimental trial lasted for about 30 days. The results showed that under the same experimental conditions, the growth rate of the fish decreased with increasing stocking density. By contrast, the feed conversion rate increased gradually with increasing stocking density. There was no significant difference (P > 0.05) in the average survival rates of the fish in each group in both trials, except Group 5 in SSS (P < 0.05).