Beyond the Price Tag: How Digestible Nutrients Drive Profitability in Grow-Finish Swine
By Thomas D’Alfonso, Ph.D., Worldwide Animal Nutrition Focus Area Director, USSEC
Most swine nutritionists know that feed cost represents the largest single expense in commercial swine production. According to Nutrient Requirements of Swine (NRC 1812) formulations, feed ingredients can account for 60% to 75% of total live production costs. With this major investment, the question to ask is NOT “What do feed ingredients cost?” The question is, “What value is the feed delivering?”
When evaluating ingredients on cost per unit of digestible nutrient,¹ soybean meal derived from U.S. Soy consistently provides the foundation for predictable performance and operational efficiency that nourishes a business.
Constant financial pressures can create the temptation to focus on reducing diet cost per metric ton. But purchasing ingredients based on price alone can create false savings, especially when calculations don’t account for nutrient digestibility1 and availability.
The true measure of feed value2 is not the ingredient’s price per metric ton, but its cost per unit of digestible nutrient, specifically, the digestible amino acids and energy that drive lean growth and carcass yield in an operation.

The Real Cost of Protein
Grow-finish pigs require precision-balanced amino acids and energy to support efficient lean tissue deposition, feed conversion and carcass uniformity. Ingredients with lower amino acid digestibility3 may appear less expensive but ultimately cost more per kilogram of usable nutrition delivered.
Example: Cost per Unit of Digestible Lysine (Source: NRC 12)
| Protein Source | Price ($/MT) | Digestible Lysine (%) | Cost per kg Digestible Lysine ($) |
| Soybean meal derived from U.S. Soy | 100 | 2.85 | 10.53 |
| Brazilian soybean meal | 94 | 2.76 | 10.65 |
| Canola meal | 30 | 1.62 | 14.20 |
| Sunflower meal | 195 | 0.99 | 19.70 |
When digestible lysine content and digestibility rates are factored into diet formulation, research1, 2 supports that soybean meal derived from U.S. Soy offers a nutritional premium which can offset a higher per-ton price. Less expensive alternatives deliver less usable protein, require more synthetic amino acid supplementation and may reduce carcass yield due to suboptimal nutrient ratios.4, 5
Formulation Reality in Grow-Finish Diets
Swine diets are formulated for precise amino acid-to-energy ratios to optimize feed conversion and lean gain. Substituting soybean meal derived from U.S. Soy with lower-cost proteins like canola meal, dried distillers grains or sunflower meal introduces risk and complexity to formulations.6, 7, 8
For example:
- Canola meal provides only about 86% lysine digestibility versus greater than 90% for U.S. soybean meal.⁹, ¹⁰
- Sunflower meal is low in lysine and energy,3 requiring you to add fat or synthetic amino acids.
- Dried distillers grains vary widely in amino acid digestibility ¹¹ and oil content, demanding frequent formulation changes.
In short, what appears cheaper per metric ton often raises total diet cost once calculations account for digestibility corrections and performance variability.

Efficiency
Feed efficiency, carcass yield and nitrogen excretion all depend on amino acid digestibility, not crude protein content. Soybean meal derived from U.S. Soy consistently delivers superior standardized ileal digestibility 3,13 for key amino acids compared to other vegetable proteins.
| Ingredient | Lysine Digestibility (%) | Methionine Digestibility (%) | Threonine Digestibility (%) |
| U.S. Soy5 | 90–92 | 90 | 86 |
| Brazilian soybean meal5 | 88 | 88 | 83 |
| Canola meal3 | 86 | 87 | 80 |
| Sunflower meal14 | 84 | 85 | 78 |
| Dried Distillers Grains15 | 82–85 | 83 | 75 |
Higher amino acid and energy digestibility means pigs absorb more usable nutrients per kilogram of feed. That translates into lower feed cost per pound of gain and improved carcass uniformity. In trials comparing protein sources, grow-finish pigs fed soybean meal derived from U.S. Soy achieved superior feed conversion ratios16 and lean gain compared to those fed South American meals.
Superior amino acid digestibility becomes even more valuable during stressful periods including respiratory challenges, heat stress or post-weaning transitions. This is when functional compounds in U.S. Soy work synergistically with its nutrient density to maintain performance when synthetics alone fall short. 18
Consistency Adds Value
The nutrient consistency of soybean meal derived from U.S. Soy,1 especially in amino acid profile, digestibility and metabolizable energy, allows for formulating diets with precision, without large safety margins. This reduces the “hidden costs” that come from variability and reformulation when using alternative ingredients.
In contrast, protein meals from other origins often show greater batch-to-batch variability in amino acid content, oil and fiber levels, forcing nutritionists to formulate conservatively and accept lower performance predictability.12, 19 Consistency equals fewer surprises and more reliable ROI for the operation.
The Economic Takeaway
Evaluating protein sources on a cost-per-metric-ton basis hides the true economics of pig performance. When expressing cost per kilogram of digestible lysine or energy, soybean meal derived from U.S. Soy consistently outperforms lower-priced alternatives – delivering the most usable nutrition per dollar spent.
When accounting for what that nutrient density is actually worth at the formulation level, soybean meal derived from U.S. Soy represents at least $20 to $25 per metric ton1 in additional feed value, an advantage that compounds across every production cycle.
Practical Takeaways
Moving from “cost per metric ton” to “cost per unit of digestible nutrition” reveals that soybean meal derived from U.S. Soy provides the most economical, consistent and performance-proven value in grow-finish swine diets. It supports improved average daily gain and feed conversion ratios, higher carcass lean percentage, lower nitrogen excretion and greater diet formulation precision.
Feed cost efficiency means extracting maximum usable nutrition per dollar invested and maximum return from every pig marketed.
By prioritizing digestible nutrient economics over ingredient price alone, operations gain improved average daily gain and feed conversion, higher carcass lean percentage, reduced environmental impact and the formulation precision that supports profitable operations.
That’s how U.S. Soy nourishes your business.
Partially funded by the Soy Checkoff
¹ Economic value and environmental impact of soybean meal in poultry and swine diets, M. Pope, R. Boyd, D. Holzgraefe, H. Monaco and M. Sifri, Journal of Applied Poultry Research, 2024
² Invited review: Amino acid bioavailability in pig feed ingredients: Terminology and application, H. H. Stein, B. Séve, M. F. Fuller, P. J. Moughan, and C. F. M. de Lange, Journal of Animal Science, 2007
³ Standardized ileal digestibility of crude protein and amino acids in soybean meal, canola, cottonseed, and sunflower products fed to finishing pigs, J. C. González-Vega, B. G. Kim, J. K. Htoo, A. Lemme and H. H. Stein, Journal of Animal Science, 2012
⁴ The evaluation of soybean meals from three major soybean-producing countries on productive performance and feeding value of pig diets, J. P. Wang, S. M. Hong, L. Yan, J. H. Cho and I. H. Kim, Journal of Animal Science, 2011
⁵ Chemical composition and amino acid digestibility of soybean meals produced in the United States, China, Argentina, Brazil, or India, L. V. Lagos, C. L. Walk, Y. Liu and H. H. Stein, Journal of Animal Science, 2017
⁶ Effect of different protein sources on growth and carcass traits in growing-finishing pigs, J. L. Shelton, M. D. Hemann, R. M. Strode, et al., Journal of Animal Science, 2001
⁷ Increased inclusion of soybean meal in diets improves gain and feed efficiency of healthy finishing pigs, E. van Heugten, U.S. Soy Technical Bulletin, United Soybean Board/USSEC, 2025
⁸ Effect of mixed meal replacement of soybean meal on growth performance, nutrient apparent digestibility, and gut microbiota of finishing pigs, Z. He, S. Liu, X. Wen, et al., Frontiers in Veterinary Science, 2024
⁹ Effects of feeding canola meal from high-protein or conventional varieties and soybean meal on growth performance and carcass characteristics of growing-finishing pigs, K. L. Little, J. D. Hancock, K. C. Behnke, et al., Journal of Animal Science, 2015
¹⁰ Local protein sources for growing-finishing pigs and their effects on growth performance and carcass quality, L. Stødkilde, T. S. Bruun, H. D. Poulsen and T. S. Nielsen, Animal, 2023
¹¹ Evaluation of corn distillers dried grains with solubles in grow-finish swine diets, S. K. Linneen, J. L. Nelssen, M. D. Tokach, et al., Swine Day 2006, Kansas State University, 2006
¹² Ileal amino acid digestibilities by pigs fed soybean meals from five major soybean-producing countries, L. K. Karr-Lilienthal, N. R. Merchen, C. M. Grieshop, et al., Journal of Animal Science, 2004
¹³ Energy concentration and amino acid digestibility in high-protein canola meal, conventional canola meal, and soybean meal fed to growing pigs, J. D. Berrocoso, O. J. Rojas, Y. Liu, J. Shoulders, J. C. González-Vega and H. H. Stein, Journal of Animal Science, 2015
¹⁴ Determination and prediction of the amino acid digestibility of sunflower seed meals in growing pigs, J D. Liu, Q. Y. Li, Z. K. Zeng, P. Li, X. Xu, H. L. Wang, S. Zhang and X. S. Piao,, Asian-Australasian Journal of Animal Sciences, 2015
¹⁵ Amino acid digestibility of distillers dried grains with solubles, produced from sorghum, a sorghum–corn blend, and corn fed to growing pigs, P. E. Urriola, D. Hoehler, C. Pedersen, H. H. Stein and G. C. Shurson, Journal of Animal Science, 2009
¹⁶ Nutrient Requirements of Swine (11th rev. ed.), National Research Council (NRC), National Academies Press, 2012
¹⁷ Impact on performance and carcass characteristics when replacing soybean meal with distillers dried grains with solubles and crystalline amino acids in diets of growing and finishing pigs, B. E. Anderson, M.S. Thesis, North Carolina State University, 2021
¹⁸ Standardized ileal digestible amino acids and digestible energy in high-fiber feed ingredients fed to growing pigs, L. A. Huber, et al., Journal of Animal Science, 2022
¹⁹ 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, 2020