Unlocking the Soy Effect: Four Pillars for Maximizing Swine Profitability with U.S. Soy
For swine producers worldwide, every nutritional decision directly impacts the bottom line in an industry facing unprecedented feed cost volatility. During the 2025 Soy Connext conference, Dr. David Rosero presented compelling research challenging traditional thinking about soybean meal’s value.
“Today, I think we lack the knowledge on the true value of soybean meal,” explains Dr. Rosero, Iowa State University assistant professor and former Technical Officer at The Hanor Company, where he oversaw nutrition programs for more than two million pigs annually. “If we let the pigs tell us the story, we can get more value from high-quality ingredients.”
His research reveals “The Soy Effect,”[1] four evidence-based pillars proving producers have significantly undervalued this critical ingredient.
The Four Pillars of the Soy Effect
Pillar 1: Energy contribution of soybean meal in commercial diets
“The energy contribution of soybean meal has been one of the most underestimated aspects of swine feed formulations,” Dr. Rosero emphasizes. “We have a pig that’s different than 20-25 years ago when research was published for NRC 2012. It’s time to update those values.”
While feed formulations traditionally value soybean meal at 77% of corn’s energy content, Rosero presented his recent research showing estimations of soybean meal energy values ranging from 82-125% of corn’s energy value[2]. This boost comes from dense amino acid profiles, lower fiber content, and functional compounds that reduce maintenance energy requirements.
During disease challenges, pigs require up to 40% more energy for immune responses. Rosero’s work has found that soybean meal’s anti-inflammatory properties redirect energy toward productive growth instead.
“It’s not just energy or amino acids—it goes beyond, giving soybean meal a better opportunity to compete in diets while delivering consistent pig responses.”
Pillar 2: Soybean meal as a functional bioactive for animal health
Beyond nutrition, soybean meal provides anti-inflammatory, antiviral, and antioxidant compounds that reduce medication needs and light-weight pigs at market. According to Rosero’s presentation, when pigs were challenged with the PRRS virus, higher isoflavone levels reduced mortality by approximately 50%.
“This is an area where we don’t know much,” Dr. Rosero admits. “We’ve seen benefits with isoflavones, but that’s just one of the multiple compounds. We still need to learn about other functional lipids and peptides—it’s a new world of compounds we don’t understand yet.”
Pillar 3: Soybean meal as a high-value protein source during late finisher diets
During his presentation at Soy Connext, Rosero highlighted that recent studies consistently show performance losses when replacing soybean meal. Substituting 40% dried distillers’ grains resulted in 3-pound reductions in final body weight, while over-reliance on synthetic amino acids led to 6-pound losses.
Dr. Rosero’s work with the original researcher behind The Soy Effect, Dr. Dean Boyd, reveals new insights: “We believe there’s a minimal level of soybean meal to achieve maximum growth performance,” particularly during late finishing phases where protein quality becomes critical for maximizing final weights and market values.
Pillar 4: Soybean meal-based diets to mitigate summer weight dip
Dr. Rosero’s team also addressed summer weight dip, seasonal challenges that cause 6-12 pound carcass weight reductions when market prices peak. Their soybean meal-based program, with minimum inclusion levels and elimination of feed intake-reducing ingredients, achieved remarkable results.
“We can capture up to $14 per pig compared to diets that didn’t offer that growth response[3]. For a 2.2 million pig operation, that’s a substantial revenue increase,” Dr. Rosero reported during the event.
He noted that including soybean meal in swine diets during hot months maintained and improved summer performance.
“Depending on market conditions, feed costs, and hog prices, soybean meal is a strategic tool to maximize revenue capture and minimize feed costs.”
Dr. Rosero also noted that consistency in ingredient quality is paramount.
“For a company of the size I used to work in, consistency in high quality might mean 2-4 points in feed conversion—$1 to $2 per head in feed costs. With 2.2 million head, that’s a big deal.”
He noted that U.S. soybean meal offers the consistency international producers need, with comprehensive quality standards providing the foundation for predictable performance.
The Science Behind the Success
For Dr. Rosero, his newest research represents a fundamental discovery. “As a scientist, what excites me is what we don’t know—understanding the biology of the pig and what role soybean meal plays. Getting to understand and put a value on that gets me excited.”
Rather than relying on theoretical calculations, Dr. Rosero encourages practical trials. “I would like to do side-by-side comparisons. See how something different impacts operations economically. Maybe save $4-5 per pig in feed costs—that would be substantial. What if you get a pound or two in final pig weight?”
His recommendation is straightforward: “I encourage people to try U.S. soybean meal and compare it to their current program.”
The research is clear—soybean meal offers value far beyond its traditional protein source role. U.S. soybean meal provides the quality, consistency, and functional benefits needed to maximize animal performance and economic returns for international pig producers ready to unlock hidden profitability.
As Dr. Rosero emphasizes, the proof is in performance. When producers give U.S. soybean meal a chance through on-farm trials, the results speak for themselves.
Learn more about Dr. Rosero and his presentation at the Soy Connext conference by visiting https://youtu.be/sRMNM4NExoQ
This article is funded in part by the soy checkoff.
[1] https://soyeffect.ussoy.org/
[2] https://soyeffect.ussoy.org/
[3] https://soyeffect.ussoy.org/