Comparison and efficacy of soy-based ingredients in practical diets for Florida pompano (Trachinotus carolinus)

Abstract Three Trials were performed to understand better how soy processed in different ways impacts the growth, feed conversion ratio, and health of the Florida pompano ( Trachinotus carolinus ). The first two growth Trials were performed to evaluate the efficacy of an open soy-based diet compared to a commercially produced, fish meal (FM)–based diet. Trial 1 compared a soy-based diet to a commercial FM-based diet using juvenile fish (23.2 ± 1.87 g) across six replicates over 42 days. The FM-based diet significantly outperformed the soy diet in final biomass ( p = 0.026), weight gain ( p = 0.006), and feed conversion ratio (FCR) ( p = 0.015). Trial 2 used larger fish (38.1 ± 0.86 g) with three replicates over 56 days and found no significant differences between diets. Histological samples of the distal intestine showed no statistical differences in symptoms conducive to soy-induced enteritis between the practical soy diet and the commercial FM diet. Trial 3 evaluated nine experimental soy-based diets in juvenile pompano (4.82 ± 0.09 g) across quadruplicate tanks for 76 days. The basal diet containing 49.97% solvent-extracted soybean meal (SBM) was compared with diets where SBM was replaced at 50% or 100% with low oligosaccharide SBM, soy protein concentrate, or enzyme-treated SBM, or at 25% or 50% with expeller-extruded SBM. No significant differences were found in weight ( p = 0.493), survival ( p = 0.925), or FCR ( p = 0.874). Histological analysis showed no adverse intestinal effects in lamina propria thickness, lamina propria cellularity, connective tissue thickening, or abundance of goblet cells.