Examination of corn fermented proteins and high protein distillers dried grains to replace fishmeal and poultry meal in juvenile rainbow trout diets

Authors: Sealey, Wendy; BOCKUS, ABIGAIL - Us Fish And Wildlife Service; TILTON, SCOTT - The Andersons, Inc, Turfand Specialty Group; GAYLORD, GIBSON - Us Fish And Wildlife Service

Submitted to: Journal of the World Aquaculture Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/7/2025
Publication Date: 10/7/2025
Citation: Sealey, W.M., Bockus, A., Tilton, S., Gaylord, G.T. 2025. Examination of corn fermented proteins and high protein distillers dried grains to replace fishmeal and poultry meal in juvenile rainbow trout diets. Journal of the World Aquaculture Society. 56: e70059. https://doi.org/10.1111/jwas.70059.
DOI: https://doi.org/10.1111/jwas.70059

Interpretive Summary: A variety of plant proteins have been investigated for their potential to reduce the dependence of aquaculture feeds on wild-harvested fish meals during the last two decades. These plant proteins include corn-based products that are produced during the production of bio ethanol for which the US is the leading global producer. To address the suitability of two novel ethanol co-products for fish, USDA ARS scientists collaborated with colleagues in the US Fish and Wildlife Service and an US based ingredient supplier to conduct a growth trial where fish meal and poultry meal were replaced with increasing levels of corn fermented protein products. The growth results from that study indicated that U.S. corn fermented proteins can be used in place of fish meal and poultry meal at inclusion levels of approximately 15% without substantially altering the production efficiency of rainbow trout. The successful incorporation of U.S. produced corn fermented proteins in aquafeeds provides corn growers alternative high value markets for their grain and rainbow trout producers the potential for increased fish feed formulation flexibility with reduced reliance on expensive animal meals.

Technical Abstract: The ability of high value plant protein concentrates to replace fish meal and other expensive animal proteins in diets for rainbow trout depends on their available nutrient composition, cost, and consistency. The aim of this study was to assess the effects of two novel corn fermented protein products (ANDVantageTM 40Y and ANDVantageTM 50Y, The Andersons, Inc.) on growth performance of juvenile rainbow trout. A 2 x 5 factorial design was applied with test products included at 0, 7.5, 15, 22.5 and 30% diet dry weight replacing dietary fish meal and poultry meal on a digestible protein (DP) basis. All diets were formulated to 42% DP and 18% crude lipid, supplemented with Lys, Met and Thr to targets of 3.8, 1.3 and 2.1%, respectively, and manufactured by cooking extrusion. Diets were randomly assigned to triplicate tanks of rainbow trout (Oncorhynchus mykiss, Troutlodge Inc., Sumner, WA) with a mean initial weight of 38 ' 0.7 g (mean ' SD). Fish were cultured in poly tanks (320 L) at n = 20 fish per tank in a recirculating system with a flow rate of 4-6 L min-1, temperature at 15 'C, and a 13:11 light:dark cycle, and fed twice daily to apparent satiation six days per week for 12 weeks. Including ANDVantage products at levels above 22.5% decreased growth (gram gain per fish, P<0.0001). A significant interaction was observed for feed conversion ratio (FCR; P<0.0001) wherein fish fed ANDVantageTM 40Y had significantly higher FCR than fish fed ANDVantageTM 50Y when fed levels above 22.5%. Optimized inclusion levels, determined by regression analysis for combined data or for each ingredient when interactive effects occurred, indicate that maximum inclusion levels for ANDVantage 40Y and ANDVantage 50Y in rainbow trout diets range from 13.5 to 21.5% depending on the performance variable assessed.