Effects of Water Temperature on Growth Performance in Juvenile Amur Sturgeon, Sterlet and Siberian Sturgeon

The effects of water temperature(15℃, 18℃, 21℃, 24℃ and 27℃) on growth performance of juvenile Amur sturgeon(Acipenser schrenckii), sterlet(A. ruthenus) and Siberian sturgeon(A.baerii) were studied in a recirculating system. The results showed that the specific growth rate in body length(SGRL) was found to be significantly higher in the juvenile Amur sturgeon in 24℃ group than in other groups(P0.05), without significant difference in specific growth rate in body weight(SGRW). Absolute growth rate in body length(AGRL) was found to be decreased with rising temperature within 18℃~27℃, significantly higher in Amur sturgeon juveniles in 15℃ group(P0.05). The absolute growth rate in body weight(AGRW) was higher in the juvenile Amur sturgeon within 18℃~24℃ than in 15℃ and 27℃ groups(P0.05). The relative growth rate in body length was found to be increased with increasing temperature within 18-24℃, significantly higher in Amur sturgeon juveniles in 15℃ and 27℃ groups(P0.05), with the optimum temperature range of 18~24℃, and the optimum growth temperature of 24℃. There was significantly higher SGRLin sterlets juveniles in18℃ group than in other temperature groups(P0.05), without significant difference in SGRW(P0.05). The AGRWwas found first increases,and then decrease from 15℃ to 24℃ in juvenile starlet, significantly higher in 18℃(0.61g/d) and 24℃(0.64g/d) groups than in other groups, the minimum AGRL(1.6mm/d) in 15℃ group, significantly lower than in other groups. The optimum growth temperature was changed from 18℃ to 24℃ for starlet juveniles, with the optimum growth temperature of 18℃. Siberian sturgeon fingerlings exposed to 21℃ showed significantly higher SGRL, AGRLand body length relative growth rate than the fish in the other groups(P0.05)within the temperature range of 15~27℃, with the minimal survival rate at 27℃. The optimum growth was observed in Siberian sturgeon fingerlings at water temperature from 15℃ to 24℃, with the optimum growth temperature of 21℃, Siberian sturgeon being a strong allometry growth model at different temperature, and different from Sterlet and Siberian sturgeons. The findings show that the 3species of sturgeon fingerlings are reared at different temperature ranges within the water temperature of 15~27℃, since the sturgeon fingerlings have various optimum growth temperature and condition factors in different temperature in early growth stage.