Replacement of Fish Meal with Soybean Meal, Alone or in Combination with Distiller's Dried Grains with Solubles in Practical Diets for Pacific White Shrimp, Litopenaeus vannamei, Grown in a Clear-Water Culture System

The objective of this study was to evaluate inclusion of distiller's dried grains with solubles (DDGS) as partial replacement of commercial, solvent-extracted soybean meal (SBM) in fish meal-free diets for Pacific white shrimp, Litopenaeus vannamei. Aquaria connected to a recirculating biofiltration system were utilized to evaluate growth, survival, and feed conversion of shrimp during the 8-wk feeding trial. Each 110-L aquarium was stocked with 15 shrimp (mean individual weight 0.99g) and fed one of five diets: a diet containing 20% fish meal (FM), which served as the control (Diet 1); a diet containing 0% FM and 52.5% SBM (Diet 2); and diets containing 0% FM and either 10, 20, or 30% DDGS as partial replacement of SBM (Diets 3, 4, and 5, respectively). Shrimp were fed according to a pre-determined feeding chart five times daily (0730, 1030, 1330, 1630, and 1930h) and there were three replicates per dietary treatment. The results from the feeding trial demonstrated that final weight, weight gain (g), and percentage weight gain were significantly higher (P<0.05) for shrimp fed Diet 1 (10.96g, 10.01g, and 1051%, respectively) compared to shrimp fed diets containing DDGS; however, shrimp fed diets containing DDGS had similar (P>0.05) final weight, weight gain (g), and percentage weight gain as shrimp fed a diet containing 0% FM and 52.5% SBM (Diet 2). Feed conversion ratio (FCR) of shrimp fed Diet 1 (2.84) was significantly lower (P<0.05) compared to shrimp fed any other diet. Survival (%) was not different (P>0.05) among treatments and averaged 77.3% for the study. This study demonstrated that practical shrimp diets containing no FM had an adverse impact on growth performance of white shrimp when grown in a clear-water system and that further research is needed to refine diet formulations when culturing shrimp in these systems when attempting to feed a diet without FM.