KSU Research Improves Hog Feed Efficiency

OMAHA (DTN) -- New research from Kansas State University (KSU) researchers could help hog producers fine-tune diets for growing pigs and improve both feed efficiency and economic returns, according to a KSU press release.

Much of the work centers around soybean meal, a major protein source in swine diets, and how it is best incorporated alongside synthetic amino acids, according to Katelyn Gaffield, assistant research professor in the Department of Animal Sciences and Industry at KSU.

"Soybean meal is one of the primary protein sources for swine diets," Gaffield said. "We are researching the consistency and quality of soybean meal so that we can integrate it appropriately into the diet."

Gaffield and KSU's applied swine nutrition team have explored multiple quality parameters, including trypsin inhibitors, which can negatively affect swine performance. Controlling such factors could improve growth rates and feed efficiency, she said.

Doctoral student Ron Navales is investigating the ratio of lysine to crude protein, a critical relationship in swine diets as producers increasingly use crystalline amino acids to meet nutritional needs. In the past, diets were formulated based on crude protein levels.

"But now, with better technology and the availability of crystalline amino acids like lysine and methionine, we can more precisely meet amino acid requirements," Navales said. "However, aggressive use of crystalline amino acids can result in reduced crude protein in the diet, and in return, could potentially impact performance."

Navales' research, which is supported by the United Soybean Board, involved feeding more than 2,500 hogs across four experiments, adjusting lysine-to-protein ratios from 85% to 115% of the current estimated requirements.

Among the most promising results is that while hogs maintained steady weight grain they consumed more feed when dietary protein was lower. The pigs are compensating to meet their nitrogen needs, which could have been supplied by an intact nitrogen source, such as soybean meal, he said.

"This shows there's a limit to how much we can replace intact proteins with synthetics," Gaffield said. "Going too low in protein might hurt feed efficiency, even if amino acid levels are technically met."

Both Gaffield and Navales said their research is directly applicable to swine producers. Results from these trials will help guide dietary formulation, particularly the balance between soybean meal and synthetic amino acids, to avoid inefficiencies that could impact profitability.

"It's practical research," Gaffield said. "We're identifying ratios that can be directly implemented by producers and nutritionists."

The research will also be validated on a commercial scale. Gaffield said the next step is to ensure the findings hold up outside of controlled university environments.

Gaffield's team is also conducting a nationwide survey backed by the United Soybean Board to evaluate the consistency and quality of soybean meal from 27 to 30 processing plants across the U.S.

This will help define U.S. soybean meal quality and examine lab-to-lab variation, she said.

Gaffield and Navales said their aim is to help swine producers make more informed, cost-effective nutrition decisions.

"Feed efficiency affects your bottom line," Navales said. "If pigs grow the same but eat more to compensate for lower protein, that affects economics."

KSU's Swine Day will be held Nov. 20. There will be sessions that day detailing the research on soybean meal quality and the optimal lysine-to-protein ratios.

For questions about KSU's 2025 Swine Day, contact Katie Smith at 785-532-1267 or katiesmith@ksu.edu.

Russ Quinn can be reached at Russ.Quinn@dtn.com

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