UNL Scientists Continue to Hone Use of Ethanol Byproducts in Cattle Feeding

UNL Scientists Continue to Hone Use of Ethanol Byproducts in Cattle Feeding

May 1, 2009

University of Nebraska-Lincoln scientists are continuing to refine how the state can best take advantage of its unique mix of corn, cattle and ethanol production. One key focus is expanding use of ethanol byproducts in cattle feeding.

"A lot of states have ethanol and grain production and some others have cattle, but Nebraska is the only state that has all three. Our goal is to figure out ways to capitalize on that advantage," said UNL animal scientist Galen Erickson. "We want to improve the use of feed byproducts produced from ethanol production, increase their use and evaluate the economics for Nebraska agricultural producers."

UNL animal scientists have been leaders for years in this field. Their pioneering studies in the 1990s proved the benefits of feeding wet byproducts to cattle instead of drying the material. Eliminating drying reduces ethanol production costs about 5% and provides an economical, high-performance feed. This work transformed wet byproducts into a feedlot staple and aided development of Nebraska's ethanol industry.

Recent efforts include development of Cattle CODE, an online computer program that feedlot operators can use to predict cattle performance and economic returns from feeding byproducts, based on individualized information such as grain, byproduct and transportation costs.

"Feeding byproducts is complex and cattle feeders need to know the bottom line. This gives it to them," said Erickson, who worked with colleagues including fellow animal scientist Terry Klopfenstein and agricultural economist Darrell Mark on the program.

UNL research by Erickson and Klopfenstein also is looking into feeding a higher percentage of ethanol byproducts to cattle. Historically, wet byproducts have comprised 15-20% of feedlot rations. Researchers hope to boost that to as much as 50%, perhaps even more.

"What happens if we feed 60, 70 or even 80%?," Erickson said.

One part of that research is gauging the impact of sulfur in diet. While sulfur is a required mineral for cattle, ingesting too much can result in sulfur toxicity, reduce feed and water intake and may cause polioencephalomalacia, a potentially fatal neurologic disease. Numerous analyses have shown that the sulfur content of distillers grains is generally four to seven times greater than that of corn.

"We have to figure out the upper level of sulfur that's fairly low risk," Erickson said.

Scientists are beginning to get some of those answers. Byproduct feeding experiments conducted by UNL found the incidence of polio in cattle with diets containing .46% or less sulfur was small -- only about .14%. Incidences of the disease increased to about .35% when cattle were fed diets ranging from 0.46% sulfur to .56% and increased to 6.06% in those fed diets with .56% or more sulfur.

Researchers also are studying the impact of fat in distillers-grains-heavy diets because too much fat in rations can harm cattle performance.

"We're trying to determine the upper limits," Erickson said.

The research is funded by the Nebraska Center for Energy Sciences Research, the Nebraska Corn Board and UNL's Programs of Excellence initiative.

Dan Moser
IANR News Service