Unmistakable cattle manure odors have become a bigger issue during the last several years as more and more people move from cities and suburbs to rural areas. Agricultural Research Service (ARS) scientists are researching various methods to reduce the unwanted odor, including the type of corn fed to animals.
At the ARS Roman L. Hruska U.S. Meat Animal Research Center in Clay Center, Neb., several ARS scientists are studying beef cattle diets to see if they can change them to reduce unpleasant odors while still raising productive animals. They found that feeding cattle high-moisture corn instead of the traditional dry-rolled corn significantly reduced the odors.
The scientists don't measure odor per se, but the compounds that might cause odor. Starch that is not digested produces many odor-causing compounds in manure. If more starch is digested, less starch is available to cause odor. Starch from dry-rolled corn does not get digested as thoroughly as that in the high-moisture corn, so cattle fed high-moisture corn are less likely to produce foul-smelling manure.
High-moisture corn is usually cheaper for cattle producers who own the corn. But for those who don't, it can become too expensive because of storage and transportation issues.
The research was conducted by postdoctoral fellow Shawn L. Archibeque, animal scientist Harvey C. Freetly, microbiologist Daniel N. Miller, and animal scientist Calvin L. Ferrell. Their results were presented earlier this year at a "Symposium on the State of the Science: Animal Manure and Waste Management," in San Antonio, Texas.
The symposium was sponsored by the National Center for Manure and Animal Waste Management, which receives funding from the USDA Cooperative State Research, Education and Extension Service.
ARS is the U.S. Department of Agriculture's chief scientific research agency.