Beyond Protein: U.S. Soy for Ruminants 

By Thomas D’Alfonso, Ph.D., Worldwide Animal Nutrition Focus Area Director, USSEC 

When formulating rations for ruminant animals, nutritionists look for more than crude protein. High-performing dairy cattle, beef cattle, sheep and goats require consistency and digestibility in their feed rations. Operations are also seeking sustainable feed ingredients – both in terms of their environmental impact and their benefits to the bottom line. 

Soybean meal derived from U.S. Soy delivers the consistency, digestibility and sustainability businesses need. 

High-Quality Protein That Works Smarter 

Solvent-extracted soybean meal contains approximately 44% to 48% crude protein and offers the greatest content of indispensable amino acids of any oilseed meal – including lysine, methionine and threonine, which are essential to animal productivity.¹ It supplies both rumen-degradable protein (RDP) to fuel microbial growth and rumen-undegradable protein (RUP) that bypasses ruminal fermentation for direct intestinal absorption.¹ 

For high-producing dairy cows, that RUP fraction matters: as productivity climbs, microbial protein alone cannot meet the cow’s metabolizable protein needs, making soybean meal a cornerstone of lactation rations across North America and much of the world.¹ It is also a preferred alternative to animal-based protein sources, which are restricted in ruminant diets in many regions.¹ 

Digestibility That Drives Feed Efficiency 

Soybean meal proteins are highly digestible in both the rumen and the small intestine. Research in lactating dairy cows shows that solvent-extracted and processed soybean meal products deliver consistent ruminal degradability and intestinal amino acid digestibility,² and that soybean meal supports milk yield comparably to or better than competing protein sources.³ Independent work also confirms that the intestinal amino acid digestibility of soybean meal exceeds that of corn distillers grains products, supporting more efficient amino acid supply per unit of crude protein fed.⁴ 

Soybean meal also retains a small amount of residual oil, typically 1.5% to 2.5%, that contributes additional energy to the diet,¹ which can help support body condition and overall energy balance, particularly in high-producing dairy cows. 

Balanced Fiber for Rumen Health 

While soybean meal is not primarily a fiber ingredient, soybean co-products such as soybean hulls are an excellent source of digestible fiber widely used in dairy rations to stretch forage supplies and reduce acidosis risk.¹ Pairing soybean meal with soybean hulls or forages helps maintain optimal digestive function across a herd. 

Consistency to Formulate Around 

For ruminant nutritionists, the value of a protein source depends as much on its consistency as on its nutrient profile. Independent analysis of commercial soybean meals from major origins found that U.S. soybean meal shows lower coefficients of variation in nutrient composition than South American meals,⁵ supporting tighter formulation and lower safety margins.⁶ 

USSEC quality tracking, which draws on U.S. Federal Grain Inspection Service data and Brazilian port surveyor data, shows U.S. soybeans averaged 10.73% moisture and 1.26% total damage compared with Brazilian averages of 12.25% moisture and 6.16% total damage in the most recent reporting period.⁷ Less moisture and less damage translate to less heat-damaged protein during processing – and more nutrient availability for animals. 

Verified Sustainability 

U.S. soybean farmers are stewards of the environment and leaders in sustainable farming methods, always working to grow more while using fewer resources. Their practices include conservation tillage to enhance soil health, cover crops to reduce erosion, carbon sequestration, water conservation and precision technology to improve efficiency.⁸ Life cycle assessment work, including land use change impact, identifies U.S. Soy as having the lowest average carbon footprint among the main origin countries supplying soybeans to the global market.⁸ 

The U.S. Soy Sustainability Assurance Protocol (SSAP) provides third-party-verified, transferable certificates that document sustainable production from farm to destination – giving operations the documentation needed to meet sustainability-focused market requirements.⁹ 

The Bottom Line for Ruminant Operations 

Soybean meal derived from U.S. Soy stands out not just for what is in it, but also for how reliably animals can use it. With high-quality protein, dependable digestibility, verified sustainability and the consistency to formulate with confidence, it earns its place at the center of modern ruminant rations. 

When incorporated at appropriate levels and balanced with fiber, energy and mineral sources, soybean meal derived from U.S. Soy is a smart investment in both animal performance and responsible sourcing. U.S. Soy nourishes business. 

What’s nourishing your business? 

Partially funded by the Soy Checkoff. 

¹ Nutritional Properties and Feeding Values of Soybeans and Their Coproducts, University of Illinois, Stein et al., Soybeans: Chemistry, Production, Processing, and Utilization, AOCS Press, pp. 615–660, 2008 

² Ruminal Degradability and Intestinal Digestibility of Protein and Amino Acids in Treated Soybean Meal Products, McGill University, Castro et al., Journal of Dairy Science 90(2):810–822, 2007 

³ Effect of Amount and Ruminal Degradability of Soybean Meal Protein on Performance of Lactating Dairy Cows, USDA Dairy Forage Research Center, Colmenero and Broderick, Journal of Dairy Science 89(5):1635–1643, 2006  

⁴ Ruminal Degradability and Intestinal Digestibility of Protein and Amino Acids in Soybean and Corn Distillers Grains Products, South Dakota State University, Mjoun et al., Journal of Dairy Science 93(9):4144–4154, 2010 

⁵ Influence of the Origin of the Beans on the Chemical Composition and Nutritive Value of Commercial Soybean Meals, Universidad Politécnica de Madrid, García-Rebollar et al., Animal Feed Science and Technology 221:245–261, 2016