New Non-GMO High Protein Soybean Meals without Anti-Nutritionals for Aquafeeds

Alejandro Buentello, VP of Research and Aquaculture Business, Schillinger Genetics, Inc.

Soybean cultivars have been selected with 15-20% higher protein content and with the difficult-to-digest carbohydrates raffinose and stachyose, as well as trypsin inhibitors significantly reduced. The defatted meal derived from these cultivars exceeds 56% in protein content and with further gentle processing will surpass 60% in crude protein (CP). Feeding trials comparing protein digestibility, metabolizable energy, mortality, FCR and growth performance have been conducted with Atlantic salmon, rainbow trout, Pacific white shrimp, European sea bass, cobia, yellowtail and red drum. Additional trials with other aquaculture species will be conducted in 2012. The search has been intensified for new soy meals and traits that will further improve the nutritive value of aquafeeds in key aquatic species. In order to expand testing efforts on aquafeeds, Schillinger Genetics (SG) has conducted replicated feeding trials utilizing “first feeding” rainbow trout fry with an average initial weight of ~ 0.1 g. Experimental diets were formulated to contain 42% CP, 15% lipid and derive the dietary protein from sardine meal (reference diet), sardine meal plus SG-cultivar 3010 (50:50) or sardine meal plus soy protein concentrate (SPC) obtained from regular commodity soybeans (also 50:50 replacement). The feeding trial was conducted over a 6-week period to allow for adequate treatment separation. Results on growth  and survival indicate that SG-3010, substituting half of the fishmeal is able to support the same growth performance as the fishmeal-based diet and a significantly higher weight gain than the SPC diet. Taken together, these results indicate that the use of SG-3010 allows for a higher fishmeal replacement level in rainbow trout diets. In addition, due to its higher protein density, lesser amounts of SG-3010 are required to meet the dietary requirement for this species. Therefore, the nutritional value of SG-3010 is significantly higher than that of SPC obtained  from conventional commodity soybeans.