Production of Low-Oil DDGS to Replace Fish Meal in Aquaculture Diets

Aquaculture

Abstract

Aquaculture is the fastest growing segment of U.S. agriculture and is set to overtake wild capture fisheries. Farmed food fish accounted for 42.2% of the 158 million tons of global fish production in 2012 (FAO 2014). Fish meal, a major protein source in both aquaculture and livestock feeds, has been subject to elevated pricing due to demand and fixed supply. Plant-based protein sources, such as distiller’s dried grains with solubles (DDGS) have shown promise as fish meal replacements at an economically feasible pricing structure. Use of traditional DDGS have been limited in aquaculture diets to approximately 20% inclusion, due to relatively low protein content, less than desirable amino acid profile, and high fiber level. Prairie AquaTech, an animal nutrition and health company has developed a novel microbial conversion process that creates ahigh protein DDGS (HP-DDGS), a protein-rich and more digestible product that may fully replace traditional fish meal-based diets. The initial objectives of the MCRPC project included: 1) the development of a 1st generation HP-DDGS, 2) a performance evaluation in a feeding trial with yellow perch (Perca flavescens), and 3) an assessment of mass/energy balance and costs. The resultant HP-DDGS product was 43.43% crude protein with 84.4% protein digestibility, a marked increased from the starting values of 31.93% crude protein and 81.84% protein digestibility. Feeding trial results demonstrated that two initial HP-DDGS products achieved similar relative growth performance to a fish meal reference diet; these products also produced a similar feed conversion ratio (FCR). The continued innovation of this novel microbial conversion process allows for a high quality, cost-effective fish meal alternative for feed manufacturers and fish and livestock producers while creating a novel market for corn producers. Phase II research will focus on process optimization and continued performance evaluation trials with commercially important fish species.

Production of low-oil/fat distillers' dried grain with solubles (DDGS) to replace fish meal in aquaculture diets

By T. Bruce, M. Brown, B. Gibbons, J. Bootsma, D. Schulz, S. Sindelar, and M. Grey.