Production performance and non-specific immunity of cage-raised red drum, Sciaenops ocellatus, fed soybean-based diets

•Approximately 86% of the digestible protein provided by fishmeal was replaced with soybean products in the diet of advanced juvenile red drum.•A non-GM soybean meal with increased protein content did not result in differences in fish performance compared to commodity soybean meal.•No significant differences due to dietary treatments were observed for growth performance and non-specific-immune responses.

A 15-week feeding trial was conducted to evaluate the replacement of fishmeal (FM) with soybean products (SP) in the diet of advanced juvenile red drum, Sciaenops ocellatus. Two dehulled, hexane-extracted SP were evaluated: commodity soybean meal [SBM; 48% crude protein (CP)] and Navita 3010 [N-3010; produced from non-genetically modified, selectively bred varieties; 54% CP]. The additive effect of a prebiotic (GroBiotic®-A; GBA) on the overall performance of red drum also was evaluated. All diets were formulated to contain 35% digestible protein (DP), 15% lipid, and an estimated 3.5 kcal DE kg− 1. The reference diet was formulated to contain 44.6% Special Select® menhaden FM and 15.0% corn protein concentrate (CPC). Three test diets (SBM, SBM + GBA, and N-3010) were formulated to contain 6.0% FM and 15.0% CPC, together providing approximately 38% of the dietary DP. The remaining 62% DP was provided by 5.7–5.8% soy protein concentrate (SPC) and the specific SP treatment. Diets were fed to apparent satiation to advanced juvenile red drum (mean ± SD = 68 ± 5.1 g initial weight) in each of four replicate 1-m3 floating-cages. After 15 weeks of feeding, no significant differences were found among treatments for all growth performance and non-specific-immunity parameters evaluated. Based on these results, SBM or N-3010 in combination with SPC can replace approximately 86% of the DP provided by FM in the diet without negatively affecting production performance and health status of advanced juvenile red drum.