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.