SBIR-STTR Award

NON-TECHNICAL SUMMARY: Soybean meal has long been a critical input for animal feed in monogastric animals (such as chickens and pigs) as it provides an ideal protein profile to promote healthy, rapid animal growth at a competitive price. More recently, aquaculture, the fastest growing commercial animal protein segment, has sought to take advantage of the protein and cost advantages of soybean meal as an affordable protein substitute to more expensive and less sustainable fish feeds. In 2013, global aquaculture feed included approximately 15 million metric tons of soybean meal, or about 525 million bushels of soybeans. With global aquaculture production poised to double in the next 20 years the need for sustainable, cost effective feed inputs will be greater than ever - and soybean-based feeds must be part of the solution. Unfortunately, soy feeds use in aquaculture remains limited due to the presence of anti-nutritional factors (ANF) including undigested oligosaccharides, lectins that damage the intestinal lining and phytate that binds to and prevents the uptake of proteins. Our ultimate goal is to generate a soybean variety (or soybean varieties) with eliminated or reduced ANFs to support increased feed conversion ratios (FCRs) and allow for greater soybean meal inclusion in feeding rations. Our project will leverage Arcadia's robust soybean TILLING library, which has enough genetic diversity to evaluate the ANF levels in plants with a range of mutations in targeted genes - thus creating the best potential to identify commercially attractive traits. More precisely, in phase 1 we will identify allelic series of nonsense and missense mutations in genes directly responsible for the synthesis of the three targeted ANFs. In phase 2, the best mutations for each of the ANF traits will be ntrogressed into an elite soybean variety. The effects of each mutation on the phenotype and agronomic characteristics of the new varieties will be evaluated individually and in combination to produce a "low ANF" variety with competitive agronomic performance. OBJECTIVES: The overall goal of our project is to enhance the nutritional efficacy of soybean-derived feeds, specifically for their use in aquaculture, and also generally for other monogastric animals. Though soybean meal is one of the main sources of protein used for the preparation of animal feeds, its use is limited by the presence of a number of antinutrient factors (ANFs). This is particularly true in aquaculture, a fast growing farming activity. Our project aims to identify the genetic variations (allelic series of nonsense and missense mutations) which may eliminate or reduce the following targeted ANFs (anti nutritional factors): Phytate, Oligosaccharides, and Lectin.

With global aquaculture production poised to double in the next 20 years the need for sustainable, cost effective feed inputs will be greater than ever - and soybean-based feeds can be part of the solution. Unfortunately, soy feeds use remains limited due to the presence of anti-nutritional factors including undigested oligosaccharides raffinose and stachyose, lectins that damage the intestinal lining, and phytate that binds to and prevents the uptake of proteins and essential cations. This is particularly prevalent for high-value carnivorous species such as salmon, char and trout where feed rations can only contain as little as 8% soy meal. Over Phase I of the project, we have identified and characterized at the molecular level allelic series of nonsense and missense mutations in the genes directly responsible for the synthesis of the targeted anti-nutritional factors. We have grown a collection of selected mutants carrying homozygous mutation for each allele of interest. In Phase II, we will fully phenotype the selected homozygotes and isolate the lines with best growth habits as source material for genetic crosses. Genetic crosses will be performed to combine mutated alleles to produce lines with: a single low anti-nutritional trait (low lectin, low oligosaccharides, low phytate), or to combine two, or finally three anti-nutritional traits (low lectin + low oligosaccharides + lower phytate). The effects of each mutation alone or in combination will be evaluated for agronomic performance. The transfer of the traits into elite varieties would start as soon as the phenotype for each trait has been assessed. By the end of Phase II we will produce enough product for a fish feeding study.