For decades, swine producers have recognized an increase in growth and performance when virginiamycin is added to their corn-soybean meal feed rations. U of I researchers have recently discovered that this increase in growth is partly due to increased ileal amino acid digestibility.

Hans Stein, U of I associate professor in the department of animal sciences, said, "Virginiamycin is a popular feed additive in swine diets throughout the world. It's typically used to achieve higher feed efficiency and results in less feed needed to put on a pound of gain."

However, until now, there was not a clear understanding of what caused this improvement.

Stein's team discovered that amino acid digestibility improved as soon as virginiamycin was added to the diet. When it was removed from the diet, digestibility returned to baseline. The effects only lasted as long as virginiamycin was included in the diet.

"This information is helpful to producers because it provides an explanation of why virginiamycin can help improve feed conversion," Stein said. "Producers can use less feed and fewer amino acids when they add this product to a diet because amino acids are better utilized by the pig."

This potential savings on formulation cost could increase use of virginiamycin in swine diets.

"We've shown it has a positive effect on digestibility," Stein said. "Now it's up to the producers to decide if it makes sense to use it from an economic standpoint. We believe it can lower diet cost a little due to this increase in digestibility."

This research was published in the Journal of Animal Science. Researchers included Laura Stewart, Beob Kim and Hans Stein of the U of I, and Brad Gramm and Ron Nimmo of Phibro Animal Health. Funding was provided by Phibro Animal Health.

Note: If no author is given, the source is cited instead.

• Cows, Sheep, Pigs
• Cell Biology
• Agriculture and Food
• Genetics
• Zoology
• Food

• Soy protein
• Food chain
• Animal husbandry
• Cereal
• Organic farming methods
• Trophic level