U.S. Soy: The Consistency Factor for Layers
By Thomas D’Alfonso, Ph.D., Worldwide Animal Nutrition Focus Area Director, USSEC
Achieving consistent laying hen performance across flocks and production cycles remains one of the biggest challenges for poultry nutritionists. Numerous nutritional and management factors influence egg production, shell quality and feed conversion efficiency. However, the reliability of protein sources represents a critical, yet often underestimated, contributor to performance consistency.1, 2
Variability in soybean meal quality3 can alter the supply of digestible amino acids delivered to birds, forcing nutritionists into reactive formulation strategies that rely on added safety margins to reduce nutritional risk.4 While these adjustments help protect against nutrient shortfalls, they also increase formulation conservatism4 and often contribute to greater performance variability, which ultimately can affect an operation’s profitability.5,6
Soybean meal sourced from different global origins can exhibit meaningful nutritional differences, particularly in metabolizable energy and digestible amino acid concentrations. 7, 8 If these differences are not accounted for during diet formulation, the supply of available nutrients to the birds may vary and potentially influence production performance. What appears to be the same ingredient on paper – soybean meal with similar crude protein percentages – can produce different performance outcomes due to variation in amino acid digestibility, processing conditions and overall nutritional consistency.9
Research Reveals Origin Differences
Because soybean meal is the primary protein source in most layer diets, these differences in amino acid composition and digestibility can alter the supply of digestible amino acids delivered to birds. Amino acid intake, particularly lysine and methionine, links closely to egg production rate, egg mass and feed efficiency in laying hens.1, 10
Consequently, soybean meals with similar crude protein values may produce different production responses if differences in amino acid digestibility and nutrient availability are not accounted for during formulation. In practice, studies comparing soybean meal sources have demonstrated that differences in ingredient quality can result in measurable changes in poultry performance.9
Real-World Impact Per Metric Ton
University of Illinois research found that soybean meal derived from U.S. Soy had significantly higher standardized ileal digestibility of lysine and most other indispensable amino acids compared with soybean meal from Brazil, Argentina, and India when fed to growing pigs. Soybean meal from the U.S. also demonstrated less variability in digestibility values than soybean meal from Argentina or India, supporting more precise and reliable feed formulation. 8
When incorporated into a layer diet, this variability changes the digestible lysine delivered to the hens. For example, at 25% soybean meal inclusion, the lowest-digestible soybean meal would reduce digestible lysine in the finished feed by about 0.0475% compared with the highest, equivalent to about 52 milligrams digestible lysine per hen per day at 110-gram feed intake.
Layer dose-response studies10 demonstrate that differences in digestible lysine supply can significantly affect egg production, egg weight, egg mass and feed efficiency. Therefore, failing to adjust formulation matrices for soybean meal digestible lysine variability can lead to measurable performance differences.
The metabolizable energy content tells a similar story. Universidad Politécnica de Madrid research reported that soybean meal derived from U.S. Soy contains greater apparent metabolizable energy, 2,334 kilocalories of apparent metabolizable energy per kilogram (kcal/kg) than soybean meals from Brazil, 2,282 kcal/kg, or Argentina, 2,277 kcal/kg.11 In practical diet formulation, these differences matter. For example, in a diet containing 30% soybean meal, using Brazilian or Argentine soybean meal without adjusting the energy matrix would result in under-formulating dietary energy compared with diets formulated with U.S. soybean meal.
In the same study, soybean meal derived from U.S. Soy also demonstrated higher digestibility of crude protein and essential amino acids, including lysine. Together, these differences indicate that soybean meals with similar crude protein levels can deliver substantially different amounts of usable energy and digestible amino acids depending on origin. As a result, the energy advantage further compounds the amino acid advantages observed for soybean meal derived from U.S. Soy, widening the nutritional gap among soybean meal sources.
Performance Impact on Layer Operations
Nutritional differences among soybean meals sourced from different countries can translate directly into measurable differences in laying hen performance. Feeding trials comparing soybean meal sources have demonstrated that hens receiving dehulled soybean meal derived from U.S. Soy produced heavier eggs than hens fed soybean meal from other origins.9
In one study, average egg weights reached 64.7 grams for hens fed soybean meal derived from U.S. Soy, compared to 63.5 grams and 62.3 grams respectively for hens fed Brazilian and Indian soybean meal. This represents a 2.4-gram advantage in egg weight for hens fed soybean meal derived from U.S. Soy.9
In the same study, hens fed soybean meal derived from U.S. Soy also demonstrated improvements in shell strength and interior egg quality, as measured by Haugh unit scores.9 Differences in feed conversion and egg mass production were also observed among soybean meal sources, highlighting the importance of ingredient quality and nutrient availability in supporting consistent layer performance.9 This feed conversion efficiency improvement can represent substantial cost savings when calculated across an entire flock.
Simplify Your Formulation Strategy
Variability in soybean meal composition among global origins can complicate feed formulation and force nutritionists to adopt risk-management strategies to ensure consistent nutrient supply. When digestible amino acid concentrations vary among ingredient batches, nutritionists often incorporate safety margins into formulation matrices to reduce the risk of nutrient deficiencies in the finished diet.4 Although these safety margins help ensure birds receive adequate nutrition, they frequently lead to conservative formulations and increased feed costs due to over-supplementation of nutrients.4
Greater consistency in soybean meal nutrient composition allows nutritionists to formulate diets closer to the birds’ actual nutrient requirements. When ingredient variability is lower, safety margins can be reduced, allowing diets to be formulated more precisely while maintaining confidence that the delivered nutrient levels will match expectations. Improved formulation precision can reduce nutrient waste, minimize unnecessary over-formulation costs, and support more efficient feed use without compromising performance.1, 10
The relatively low variability in nutrient composition of soybean meal derived from U.S Soy enables nutritionists to maintain consistent ingredient matrix values across feed formulations and production regions.7,8
In contrast, soybean meal from some alternative origins exhibits greater variability in nutrient composition, requiring additional adjustments to formulation matrices to account for differences among suppliers or regions.7,8
This exceptional reliability in nutrient composition of soybean meal derived from U.S. Soy allows producers to formulate diets with greater precision, reducing the need for expensive safety margins and optimizing overall feed efficiency.
U.S. Soy Nourishes Your Business
The nutritional value of soybean meal is influenced both by soybean genetics and agronomic conditions and also by processing conditions during oil extraction. Proper heat treatment during soybean meal processing is essential to maximize protein availability while minimizing antinutritional factors such as trypsin inhibitors.3 Processing quality indicators including urease activity, protein dispersibility index (PDI) and KOH protein solubility commonly verify that soybean meal has been processed adequately and help maintain consistent protein quality and amino acid digestibility across production batches.3 ,12 Differences in processing conditions and protein quality indicators can directly influence amino acid digestibility and metabolizable energy availability in poultry diets, thereby affecting nutrient supply to the bird.7,11
Consistency in nutrient composition is essential for predictable poultry performance and accurate feed formulation. Nutritionists rely on ingredients with well-defined nutrient specifications so that diets can be formulated precisely to meet the birds’ nutrient requirements. When ingredient nutrient values vary substantially, nutritionists often incorporate safety margins into feed formulations to reduce the risk of nutrient deficiencies, which can increase feed costs and reduce formulation efficiency.4
Greater consistency in soybean meal composition allows nutritionists to formulate diets closer to actual nutrient requirements while maintaining confidence that the delivered nutrition will support consistent egg production, egg mass and feed efficiency in laying hens.1, 10 Reliable ingredient quality therefore allows nutritionists to focus on optimizing nutrient supply for performance rather than managing variability in raw materials.
Partially funded by the Soy Checkoff
1 Commercial Poultry Nutrition, 3rd ed., S. Leeson and J. D. Summers, University Books, Guelph, Ontario, Canada, 2005
2 Raw material nutrient variability has substantial impact on the potential profitability of chicken meat production, A. F. Moss, P. V. Chrystal, T. M. Crowley and G. M. Pesti, Journal of Applied Poultry Research, 30(1): 100–112, 2021
3 Influence of the origin of the beans on the chemical composition and nutritive value of soybean meals, P. García-Rebollar, L. Cámara, R. Lázaro, and G. G. Mateos, Animal Feed Science and Technology, 221, 245–261, 2016
4 The future of feed formulation for poultry: Toward more sustainable production of meat and eggs, G. M. Pesti, and M. Choct, Animal Nutrition, 15:71–87, 2023
5 Chemical composition, protein quality, and nutritive value of commercial soybean meals produced from beans from different countries: A meta-analytical study, M. A. Ibáñez, C. de Blas, L. Cámara and G. G. Mateos, Animal Feed Science and Technology, 267:114531, 2020
6 The future of animal protein: implications of ingredient variability for poultry nutrition, A. F. Moss, P. V. Chrystal and P. H. Selle, Animal Production Science, 61: 376–388, 2021
7 Nutrient analysis, metabolizable energy, and digestible amino acids of soybean meals of different origins for broilers, V. Ravindran, M. R. Abdollahi and S. M. Bootwalla, Poultry Science, 93(10), 2567–2577, 2014
8 Chemical composition and amino acid digestibility of soybean meal produced in the United States, China, Argentina, Brazil, or India, L. V. Lagos and H. H. Stein, Journal of Animal Science, 95:1626–1636, 2014
9 Effects of three different soybean meal sources on layer and broiler performance, Y. H. Park, H. K. Kim, H. S. Kim, H. S. Lee, I. S. Shin and K. Y. Whang, Asian-Australasian Journal of Animal Sciences, 15(2), 254–265 (page 260), 2002
10 Evaluation of lysine requirement of the commercial layer, R. H. Harms and G. B. Russell, Poultry Science, 79:147–150, 2000.
11 Apparent metabolizable energy and ileal amino acid digestibility of commercial soybean meal of different origins in broiler, L. Aguirre, L. Camara, A. Smith, G. Fondevila and G. G. Mateos, Poultry Science, 103:103786, 2024
12 Chemical composition and protein quality comparisons of soybeans and soybean meals from five leading soybean-producing countries, L. K. Karr-Lilienthal, C. M. Grieshop, N. R. Merchen, D. C. Mahan and G. C. Fahey, Jr., Journal of Agricultural and Food Chemistry, 52(20), 6193–6199, 2004