Beef: Impact of feeding cattle low test weight corn

By Dr. Jeannine P. Schweohofer, MSUE Beef Educator

With the cool and wet growing season we saw this past year, many producers harvested low test weight corn and are feeding it out this season. Low test weight corn, corn with less than 54 lb/bu, has less starch and more fi ber available than U.S. No. 1 corn (. 56 lb/bu) or U.S. No. 2 corn (. 54 lb/bu) and is often fed to livestock. Grain buyers typically dock heavily for corn with low test weights and(or) high moisture content.

Feeding this corn to cattle appears to be one of the best uses for low test weight corn and allows the producer to maximize the value of their corn.

Low test weight corn is often associated with higher protein, although some samples from South Dakota State University research found the protein to be lower, even as low as 7.5%. If you balance a diet using book values for corn (9.5 to 10.1% crude protein) and your actual value is much lower, this can lead to a defi ciency of protein in the ration and

decreased animal performance.

Research from North Dakota State University found that low test weight corn (39.1 lb/bu) was higher in protein (11.3% crude protein) but had no affect on dry-matter intake, gain, or net energy for gain. In the same study, they found improved feed to gain ratios in cattle fed low test weight corn. They concluded that feeding low test weight corn to growing steers is

comparable to feeding regular corn.

In a two-year research study from Nebraska, low test weight corn was fed in grower and fi nisher diets. They found average daily gain and feed effi ciency to be as good with the low test weight corn as the regular test weight corn when included in growing and fi nishing diets. They also found increased average daily gain in the finishing steers fed low test weight corn in year one of the trial, but not in year two or when using combined data from year one and two. Hot carcass weights increased in cattle fed low test weight corn using combined data from both years. Other carcass data results were similar for cattle fed low test weight corn or regular corn. These authors con- cluded that feeding low test weight corn of 46 lb/bu or greater resulted in similar results to feeding U.S. No. 2 corn to growing and fi nishing cattle.

Feeding low test weight corn to cattle can have desirable results. However, it is important to have your feed analyzed so that you know what you are feeding and that the ration is properly balanced. Another important thing to remember, especially with low test weight corn, is to feed by actual weight (lb) and not volume. It takes more volume of low test weight corn to equal a bushel. Feeding by volume could result in not delivering enough feed to the cattle to reach their optimal intake and performance.

Contact your local livestock extension educator for more information regarding sampling and analysis of feedstuffs.