by Dr. James I. Sprague, Livestock Nutritionist

Moisture -- 30 percent or more at harvest
Nutritionist and experienced cattle feeders agree that the moisture in corn that is ground, ensiled and stored as high moisture must be 30 percent or more. This fact was emphasized by Dr. Steve Soderlund of Pioneer Hi-Bred at a meeting in Garden City, Kansas at the 2004 Beef Empire Days. This confirmed information shared by nutritionist in Kansas and Nebraska, plus my own experience. Lower moisture will result in inferior feed conversion of finishing cattle. Check with your nutritionist for their experience and recommendations.

Speed of harvest important
Speed of harvest, grinding and storage in the bunkers silos is important. If the harvest is delayed because of weather, water is added back to get the corn to 30 percent, but this takes time and the product may still not be as efficient as early harvested corn at 30 percent or more. Some feedyards cut off delivery of corn at 28 percent moisture or discount the price if it goes below 28 percent. Finding varieties with slow dry-down is helpful to extend the harvest period.

Adding water is difficult
My experience has found the addition of water is often erratic for corn below 28 percent. Because of the rapid speed of harvest, a “garden hose guessing system” does not work. For example, a semi-truck load of 25 percent moisture corn weighing 50000 pounds requires 3750 lbs (469 gallons) of water to bring the moisture of the final product up an additional 5 percent. As a “rule of thumb” when adding one point of moisture it takes 1.5 points of added water. And then evaporation during the packing process will lose some of the added moisture. I suggest adding an extra one or two percent of moisture to overcome evaporation. Therefore, if water is added important considerations are:
(1) an adequate supply of water,
(2) pumps with enough volume,
(3) and equipment for adding the water uniformly as the corn is ground.

The interaction of grind and moisture
A combination of uniform particle sizes along with adequate moisture leads to efficient rations that will compete with steam flaked corn programs.

Feed efficiency of the starch in the corn is better with finer particles of High Moisture moisture corn, but the finer particle of corn require rations with more roughage to prevent digestive problems. Coarser processed HM corn can be fed with little roughage.

Hammer milling with large units was the first type of processing used for ground ensiled high moisture corn. Roller mills with differential drives are also used for processing. The roller mills give a combination of a cutting and a grinding action to create some fine particles to help exclude air from the pack.
The management of the roller mills is one of the critical steps in processing high moisture corn. Because of the need for speed at harvest, many times I have observed the rolls are opened up and more whole kernels and large pieces are produced rather than a more consistent product. Particle sizes need to be evaluated during the processing to insure uniformity. ©

Dr. Sprague welcomes questions or comments on his articles. He can be reached at 316-283-8692 or by writing to him at 625 Grandview Avenue, Newton, Kansas, 67114.