Growth and feed efficiency of white sturgeon ( Acipenser transmontanus) sub-yearlings at different feeding rates

Abstract

Eight groups of 30 white sturgeon with an average individual weight of 0.25 kg were fed at four different rates in a Latin square experiment for four 2-week periods. The four feeding rates (FR) were 0.5, 1.0, 1.5 and 2.0% of the total body weight per day (BW/day) of fish in a tank, and rations were corrected daily for expected growth. The experiment was conducted with two randomized blocks, and the feeding rates were changed within each block at the beginning of each subsequent period. The mean percent body weight increases (%BWI) for the four periods at the different feeding rates were: 3.6% (FR = 0.5%), 13.6% (FR = 1.0%), 22.3% (FR = 1.5%), and 27.1% (FR = 2.0%); where the corresponding values of feed efficiency (FE) were 0.54, 0.99, 1.04, and 0.92, respectively. The mean %BWI were significantly ( P < 0.05) different betwen the four feeding rates, but only the mean FE obtained from sturgeon fed 0.5% BW/day was significantly different from the others. Neither initial body weight nor feeding period had a significant effect on the %BWI or FE, and no significant interactions were seen. The results suggest an optimal feeding rate between 1.5 and 2.0% BW/day for white sturgeon between 0.25 and 0.5 kg at 18° C.