June 11, 2008
Ethanol byproducts could cut cattle feed costs
CARBONDALE, Ill. -- They’re called “distiller’s grains,” though they come from ethanol plants, not breweries. Rebecca L. Atkinson, a beef nutritionist in Southern Illinois University Carbondale’s College of Agricultural Sciences, believes these ethanol byproducts could cut feed costs dramatically for beef cattle and cow-calf operations, creating a valuable market for what would otherwise be ethanol waste.
“Using distiller’s grains as a protein or energy supplement is nothing new -- researchers have been doing studies with them for 20 years,” Atkinson said.
“But because the fermentation process has changed, we’re looking at them again. We do know we can feed them -- the question is, at what level can we feed them without having negative effects?”
Distiller’s grains come either wet or dried, depending on the fermentation process. The dried stuff stores better, ships cheaper and blends more easily with other dietary ingredients. But much of the earlier research has been done on the wet variety.
Atkinson is conducting two dietary studies involving dried distiller’s grains with funding from the Council on Food and Agricultural Research, the National Cattleman Beef Association and the Illinois Beef Association.
One focuses on the quality of meat produced from steers fed rations that include a high percentage of such grains. The other looks at the effects of this supplement on pregnant and milk-producing cows and on their subsequent conception rates.
“We’re trying to encompass the whole beef industry rather than just a segment,” Atkinson said.
“While there has been research on adding wet distiller’s grains in beef feedlot diets, there is not much on dried grains and nothing on including any kind of distiller’s grains in the diets of gestating or lactating beef cows.”
Nor does anyone know just how much of the stuff can stand in for the more-expensive corn.
“In both studies, we’re trying to determine the optimum inclusion rate,” Atkinson said.
She also wants to know if steers on a diet that includes distiller’s grains will produce meat that not only is tender, juicy and nicely marbled but healthier, too. Some research has indicated that distiller’s grains in the diet boost the production of polyunsaturated fatty acids that are good for the heart and arteries. She’s checking for evidence of that in her lab.
“If dried distiller’s grains increase the content of unsaturated fatty acids and decrease saturated fatty acids, then retail cuts from these animals can be sold as a value-added products -- and would give consumers an alternative to fish,” Atkinson said.
Traditional rations for cattle include both soybean meal for protein and corn for energy.
“The nice thing about distiller’s grains is they’re two for one -- they can provide both energy and protein,” Atkinson said.
“The thing you have to be careful of on the cow/calf side of things is that if you feed it as an energy source, you may overfeed protein. That might mean a larger fetus, which could result in problems with labor and delivery.
“On the steer side, there are concerns about increasing sulfur content if the diet contains more than 40 percent distiller’s grains -- too much sulfur can lead to a condition called the ‘blind staggers.’”
While Atkinson’s studies won’t wind up till the end of the year, she finds early results for the steer study encouraging. She has been able to push the distiller’s grains portion of their diet to 70 percent with no ill effects.
“The cattle are eating, none of them have showed sulfur toxicity problems -- that’s been the biggest surprise,” she said.
“We thought there might be some decrease in weight gain, but they’re still gaining three or more pounds per day.”
She’s also pleased with preliminary data on meat quality.
“All graded low choice or better with some grading prime -- that’s very good,” she said.