Podcast: Uniformity starts in the feed bin - U.S. Soybean Meal protects swine performance through stress

6 January 2026

6 minute read

By: USSEC

North America

When respiratory disease or summer heat strikes a herd, the real damage is often measured not just in health challenges, but in lost performance, uneven growth and the logistical headaches that follow. Feed intake drops, growth slows and variation widens, forcing producers into multiple marketing groups that impact time, profits and revenue.

For Dr. Tom D’Alfonso, Worldwide Director of Animal Nutrition at the U.S. Soybean Export Council (USSEC), the antidote to that cycle of unpredictability begins with a dependable nutritional foundation: consistent, highly digestible soybean meal derived from U.S. Soy.

When a herd encounters health or weather stress, D’Alfonso explains that the earliest signs usually show up in disrupted feed intake and bodyweight variation across the herd. 

“Let's start with the fact that you have a population of animals, and not all the animals are affected in the same way,” he said. “The first thing you may notice is feed consumption going down. If you're keeping track of body weights, you'll see that body weights are dropping off, but it's uniformity that is often the clearest picture that something's going on with a herd. You can sometimes visually see that a portion of the population is being affected by some kind of challenge, and the next step is to do something about it.” 

That drop in uniformity touches every step of pig production. 

“Having a consistent diet, a consistent environment and consistent health among the animals in the herd makes it so much easier to plan and execute a feeding program,” D’Alfonso noted. 

Because modern feeding programs are built on tight growth curves and intake assumptions, early-stage deviation snowballs quickly. 

“When there's variability in early animal production, it carries over to the next feeding program, the next feed type, and it creates a domino effect that impacts not just the pigs and profitability but the whole value chain,” he said. 

How respiratory disease sets up vulnerability to heat stress

Research shows that pigs fighting respiratory challenges early in the production cycle face compounded performance losses months later when summer heat arrives. D’Alfonso explains: “The research done by several other scientists in the swine nutrition space have shown that there's a complex relationship between respiratory challenges early in the production cycle, during the winter or spring, and then how those animals are affected months later when the weather gets hot. They become much more susceptible to heat stress. It becomes harder to bring them back up to performance.” 

But nutrition strategy, specifically soybean meal inclusion level, can change that trajectory.

“One way to solve this issue is by having good inclusion rates of 25-30% soybean meal that is high quality. And by that, we're talking about soybean meal made from U.S. Soy,” he said. 

When temperatures rise, feed intake naturally declines across all livestock species. U.S. soybean meal helps maintain performance not by increasing crude protein, but by delivering highly digestible amino acids and energy more efficiently. 

“It was the higher inclusion rates of high-quality soybean meal that brought the performance back up,” he said. “Research shows it's not just the level of amino acids and calories, it's the quality, digestibility and consistency, and it's also the functional compounds found in U.S. Soy that are bringing digestive health.” 

Why U.S. Soy is more consistent

The defining strength of U.S. soybean meal is its predictability, rooted not in feed mill processing but in what happens on the farm. 

“It all goes back to the sustainable farming practices of the U.S. Soy farmer,” D’Alfonso said. “Soybeans grown in the United States come from family-owned farms. More than 95% of all the soybean farms are family-owned, and they are multi-generational.” 

That attention to soil and precision input management and long-term perspective are major contributors to nutrient uniformity. Another critical advantage, he noted, is natural field drying of U.S. Soy. 

“The soybeans grown in the United States do not require mechanical drying. They dry naturally in the field. Whereas soybeans coming from tropical areas, particularly Brazil, have very high moisture. They require mechanical drying.” 

That drying process often involves wood-fired heat in tropical regions and creates inconsistency in amino acid digestibility. 

“You get some that are not dried enough, you get some that are over dried and some that are over-dried, meaning heat damaged,” he said. 

Combined with superior handling infrastructure, fewer damaged beans move through the system. 

“The resiliency of our supply chain – the roads, the rivers, and the railways – are just in much better shape than in other countries. We have an established infrastructure and processes to easily move large quantities of grain from fields all over the country to wherever they are needed. So, there's a lot less nutrient damage to the bean.” 

How high inclusion improves performance and profitability

Years of research and commercial performance data point to significant gains when inclusion rates reach 20-30% or higher depending on stage of growth. At those levels, pigs facing respiratory disease required dramatically less feed to reach target weights. 

“Pigs fed higher inclusion rates alleviates the disease symptoms at that time,” D’Alfonso said. 

One study demonstrated an improvement equating to 6 kilograms or 13.2 pounds of feed saved per pig. 

“We'll multiply that by the price per pound of pork,” he said. “Addressing uniformity can be worth $1-2 per pig in a herd. When there is a challenge like respiratory disease, that value can go up from $1-2 per pig to $10 per pig. Add on the compounding effect of heat stress and it could be $14 per pig. Keeping a high inclusion rate of soybean meal made from US soy can make a big difference in your bottom line.” 

The implications for processors and packers are just as significant. 

“Hitting that target weight range and hitting the target lean versus fat ratio is where the biggest revenue occurs,” D’Alfonso explained. “If the pigs get to the processing plant and their body weight is really mixed, you're not getting the value that you could have with a more uniform herd.” 

What do functional compounds do? 

Beyond amino acids, U.S. soybean meal contains bioactive ingredients that help pigs withstand phases of stress, like disease challenges and heat stress. 

“There are a number of functional compounds in soybean meal like isoflavones, saponins and others that help build immune response and reduce inflammation,” he said. “When you reduce inflammation, you're improving digestibility. Inflammation is important. Inflammation in tissue is a sign that the body's fighting something and it takes energy to do that” 

The support functional compounds provide strengthens gut integrity and health which is critical during disease and heat exposure. 

Rethinking crude protein

For nutritionists evaluating their protein program, D’Alfonso offers a challenge to outdated thinking: “The methods that we use are over 100 years old. We’re not actually measuring crude protein. We’re measuring nitrogen and multiplying it by a coefficient. This metric is inaccurate and no longer relevant.”

Instead, he emphasizes accuracy in essential amino acids, digestible energy and functional compounds. 

“Focus on the consistency and balance of the essential amino acids and getting the right values for metabolizing energy in the feed formulation. You'll capture lower feed costs and better animal performance,” he said. 

Key takeaway for producers and nutritionists

For operations pushing efficiency amid tight margins, performance security is measured in the ability to maintain uniform growth through environmental and health volatility. And that relies on a dependable nutritional base.

D’Alfonso summarized the message clearly: “The animals can do it. They just need the right fuel.” 

This information was partially funded by the U.S Soybean Checkoff. For more information, visit www.ussec.org. 

Rosero, D. (2025, August 21). Benefits of Soy in Animal Diets: Recent Learnings of Using Soybean Meal in Swine Diets. Slide 23,"Summer SBM-based Diet Program: Revenue." “SoyConnext 2025, U.S. Soybean Export Council, Washington, DC.