This article is a summary of the 2018 Nebraska Beef Cattle Report “Effects of Kernel Processing at Harvest of Brown Midrib Corn Silage on Finishing Performance of Steers.” Lauren A. Ovinge, F. Henry Hilscher, Curtis J. Bittner, Bradley M. Boyd, John N. Anderson and Galen E. Erickson were collaborators on this research study and report.
Corn silage is often used in beef cattle diets as a roughage source. Increasing the nutrients available from corn silage through genetic improvement and processing are two ways that feed quality can be improved.
Research conducted by the University of Nebraska-Lincoln compared three different corn hybrids and evaluated the impact of kernel processing at harvest on silage quality. The three hybrids evaluated included a control variety, a brown midrib variety and a brown midrib variety with a softer endosperm. Half of each of the hybrids planted were harvested with kernel processing and the other half without, resulting in six different silages to compare.
Kernel processing involves putting harvested corn through a counter-rotating roller that cracks or flattens corn kernels between the cutterhead and blower.
These three hybrids were harvested at the Eastern Nebraska Research and Education Center near Mead in September 2016 and stored in sealed AgBags.
After the silage fermented, 360 crossbred yearling steers averaging 882 pounds were divided into 36 pens with 10 steers per pen. The 36 pens were divided equally across the three hybrids with 12 pens per hybrid. Each hybrid was further divided with six of the pens fed silage that was kernel-processed, and six of the pens fed silage that wasn’t. The corn silage was fed as 40% of a finishing diet. The cattle were fed for 104 days prior to harvest.
Cattle fed the two hybrid varieties with the brown midrib trait had improved average daily gains and lower feed to gain when compared to the control variety of corn silage.
Across the three hybrids, kernel processing tended to reduce feed intake, and there was no difference in average daily gain when compared to non-processed silage. As a result, there was a 2.6% improvement in efficiency when kernel processed silage was fed at 40% of the diet. This calculates to an estimated improvement of 6.5% (2.5/0.4) in efficiency for silage that was kernel-processed compared to not processing the silage.
This research indicates kernel processing can improve the quality of silage as feed in beef cattle diets across corn hybrids – including those with brown midrib traits. Kernel processing can have additional benefits as well, like breaking up cobs into smaller pieces and crushing plants, which can improve silo compaction. However, kernel processing at the time of silage harvest does increase cost. The cost of kernel processing should be compared to the expected value to be gained from feed improvement to determine if the additional cost is justified.
Berger is a Nebraska Extension beef educator. This report comes from UNL BeefWatch.