Replacement of Menhaden Fish Meal Protein by Solvent-Extracted Soybean Meal Protein in the Diet of Juvenile Black Sea Bass Supplemented with or without Squid Meal, Krill Meal, Methionine, and Lysine

Three experiments were conducted to determine the extent to which menhaden fish meal protein (FMP) can be replaced by solvent-extracted soybean meal protein (SBP) in the diet of juvenile black sea bass Centropristis striata. Diets were formulated replacing FMP by SBP at 0, 10, 20, 30, 40, 50, and 60% (experiment 1) and 0, 60, 70, 80, 90, and 100% (experiment 2), with supplementation with squid meal, krill meal, and attractants in both experiments. Experiment 3 was designed to replace FMP by SBP at 40, 50, 60, 70, and 80% without supplemental squid and krill meal and at 60% and 70% with supplemental methionine and lysine. Diets were fed twice daily to triplicate groups of fish (N = 15 per group) in 75-L tanks containing recirculating seawater. Fish were fed for 6, 10, and 8 weeks in experiments 1, 2, and 3, respectively. No significant differences in body weight gain, feed efficiency, and survival were observed among treatments in experiment 1. In experiment 2, no significant differences in percent weight gain were observed among fish fed diets replacing FMP at 0, 60, and 70%. In experiment 3, body weight gain was not significantly different for fish fed supplemental methionine and lysine in 70% SBP diets compared with fish fed 0% SBP diets. No significant differences were observed in whole-body n-3 polyunsaturated fatty acids among treatments in experiment 2. Broken-line regression of the specific growth rate data suggested that the maximum level of FMP replacement with SBP in black sea bass diets was 67.6-68.4% with 75 g/kg squid meal and 50 g/kg krill meal in the diet and 57.2-58.0% without squid and krill meal supplementation.