Partial replacement of fishmeal, poultry by-product meal and soy protein concentrate with two non-genetically modified soybean cultivars in diets for juvenile cobia, Rachycentron canadum Aaron M. Watson a, ⁎, Alejandro Buentello a,b , Allen R. Place a a Institute of Marine and Environmental Technology, University of Maryland Center for Environmental Science, 701 East Pratt St., Baltimore, MD 21202, United States b Schillinger Genetics and Navita Premium Feed Ingredients, 4401 Westown Parkway, Suite 225, West Des Moines, IA 50266, United States abstract article info Article history: Received 18 February 2014 Received in revised form 14 July 2014 Accepted 1 August 2014 Available online 12 August 2014 Keywords: Cobia Non-genetically modified soybean meal Fishmeal replacement Soy protein concentrate replacement Poultry by-product meal replacement Fishmeal (FM) replacement in diets for intensive aquaculture has become a high priority area for the global aquaculture industry. In this study, a twelve week growth trial was conducted with juvenile cobia (18 g initial weight) to examine the effects of non-genetically modified soybean meals as potential replacement protein sources. Genetically modified (GM) crops and their intended and unintended effects have become major topics of controversy worldwide, with several regions banning their use in food and feeds. Therefore, it is especially critical to develop and evaluate non-GM feedstuffs for use in aquaculture diets where GM products are prohibited as the global aquaculture industry continues its expansion to meet increasing demands. Navita Premium Feed Ingredients (NPFI's) 3010 solvent extracted meal and 3032 cold-pressed cake meal were utilized to replace 50, 60 or 70% and 40, 50, or 60% of FM protein, respectively and were compared to a FM based reference formulation. None of the experimental diets performed significantly different from the reference diet in terms of weight gain (WG) or specific growth rate (SGR). However the 3010 50% diet performed signifi- cantly better than the 3032 50 and 60% diets in regard to WG, SGR, and protein efficiency. There were no significant differences between the seven diets at the conclusion of the trial in regard to their effects on filet quality as determined by organoleptic testing. These two non-GM soybean protein sources appear to be valuable FM replacement options for juvenile cobia, with none of the typical indicators of intestinal enteritis developing as has been observed in various other teleost species when high quantities of commodity soybean meal have been utilized. © 2014 Elsevier B.V. All rights reserved. 1. Introduction As the world's population and protein demands continue to increase, more pressure is placed on the aquaculture industry to supply safe, sustainable seafood. However, with capture fisheries at their maximum sustainable levels since the mid-1980s, or with declining yields, fishmeal (FM) and fish oil (FO) production has remained static over much of the last decade (Metian, 2009). The urgency to substitute FM with plant products in aquafeeds was recently emphasized by chief publications on fish and shrimp nutrition (Naylor et al., 2009; NRC, 2011). Without suitable FM replacements the aquaculture industry will be unable to expand to meet current and anticipated global needs. Several potential protein replacements can be derived from marine and terrestrial sources such as by-products from animal production, seafood processing, algal meals, and algal biomass as well as by- products from the growing biofuel industry (FAO, 2012). The most abundant, accessible, and sustainable source of proteins, however, is terrestrial plant sources. Several issues arise with replacing FM with any alternative protein source. Amino acid profile, protein density and the lack of polyunsaturated fatty acids as well as the presence of anti-nutritional factors (ANFs) are a few of the challenges that must be addressed when utilizing high inclusions of plant proteins (Francis et al., 2001). Among these ANFs, protease inhibitors such as those of trypsin, chymotrypsin and elastase, hormonal inhibitors like glucosinolates, unavailable phosphorus complexed as phytate, high fiber levels, and complex carbohydrates may all have negative effects on palatability, digestibility and fish growth. The negative effects are especially detrimental to high-value marine carnivores that may not possess the required digestive capabilities to process and assimilate the carbohydrate fraction present in vegetable protein feedstuffs. Some effects of ANFs can be mitigated or eliminated through processing, thus producing acceptable feed-grade meals from various plant sources. However, in deactivating or eliminating ANFs, processing methods such Aquaculture 434 (2014) 129–136 ⁎ Corresponding author at: Marine Resources Research Institute, South Carolina Department of Natural Resources, 217 Fort Johnson Rd., Charleston, SC 29412, United States. Tel.: +1 843 953 0462. E-mail addresses: abuentello@schillgen.com, WatsonA@dnr.sc.gov (A.M. Watson). http://dx.doi.org/10.1016/j.aquaculture.2014.08.003 0044-8486/© 2014 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Aquaculture journal homepage: www.elsevier.com/locate/aqua-online