Effects of ration and temperature on growth of age-0 Atlantic sturgeon

Our objective was to gain insight into the optimum temperature and ration f or growth of age-0 Atlantic sturgeon Acipenser oxyrinchus in culture. We co nducted two trials, each for 8 weeks. Trial 1 started with 60-g fish, trial 2 started with 0.3-g fish. Water temperatures of 15, 17, and 19 degrees C were used separately in each trial. Rations (dry food : wet weight of fish) for 60-g fish were 0.5, 1.0, and 1.5% of biomass per day; for 0.3-g fish, rations were 3, 5, and 7% of biomass per day. We set up three tank replicat es, of equal fish biomass, at each combination of temperature and ration. T he highest growth rate in trial 1 (for 60-g fish) was 0.014/d at 15 degrees C and the 1.5% ration, although this growth rate was not significantly dif ferent from the growth rate at 17 degrees C and 1.5% ration or at 17 degree s C and 1.0% ration. The highest growth rate in trial 2 (for 0.3-g fish) wa s 0.067/d at 19 degrees C and the 7.0% ration. Instantaneous growth at thes e conditions was significantly different from all other combinations of tem perature and ration. Although these results may not completely define the t emperature and ration under which fish could achieve maximum growth rate, t hey provide a solid starting point for further development of Atlantic stur geon culture.