Strategies for Supplementing Cows on Corn Residue
(from the Summer 2016 issue of The Central Grasslands Forum)
Michael Undi, Animal Scientist, CGREC
Corn residue, which remains in the field after corn harvest, is a readily available feed resource for winter grazing cattle in North Dakota. Corn residue includes the stalk, leaf, husk, cob and grain from ear drop. The nutritional value of corn residue depends on the amount of residue components available for grazing. Components with the highest nutrient content are the leaf and ear. The husk is low in protein but has a good energy profile, while the cob and stalk are poor in protein and energy. The residue can be used to extend the grazing season for beef cows during fall and early winter.
Supplementing cows on corn residue depends on when the grazing is initiated. A recent study at the CGREC has shown that early to mid gestation cows can maintain and gain body condition while grazing corn residue in early fall, although supplementation will be required in late fall and winter. Several methods can be used to accomplish this task. Keep in mind that the method of supplementation used should not increase labor requirements for the producer.
The options are: *Supplementing with corn dry distillers grains with solubles (DDGS), which can be fed every third day. Feeding every third day reduces the frequency of pasture visits required by the producer to feed the supplement. Current DDGS pricing, even on the rise, still makes it a highly competitive supplement in North Dakota.
*Growing a cover crop in association with corn. After harvest, the corn residue/cover crop combination provides a high-quality feed to grazing cows. Corn residue and cover crops can be complementary, with the high protein content and digestibility of the cover crop making up for the low protein content and digestibility of corn residue.
*Feeding a good-quality legume hay to cows grazing corn residue. The hay can be rolled out onto the corn field, spread using a bale processor or placed as a whole bale. Ensure that hay is only a supplement and not the main feed source.
A study to evaluate supplementation strategies will start in the fall of 2016 at the Central Grasslands Research Extension Center. We will evaluate corn DDGS, alfalfa hay and a cover crop cocktail of rye, brassicas (turnips, rape, hybrids and radishes) and some clovers as supplements for cows grazing corn residue. Cow performance, as well as soil health benefits and the economics of these strategies, will be evaluated. For more information, contact us at email@example.com
Photos by Michael Undi and Fara Brummer, CGREC