Supplementing DDG’s to Beef Cows Grazing Cornstalks

Byron Leu, Dan Loy, and Joe Sellers, Beef Field Specialists, Southeast

Problem Statement: 

Controlling feed costs is imperative for cow-calf producers to remain cost-competitive.  Feed costs typically average over 60% of the total cow herd cost—with many Iowa producers spending over $0.60 per cow day on summer grazing costs and over $1.50 per cow day in winter feed costs.  During fall and early winter, these projected costs can be significantly reduced by utilizing corn stalks.  Stored feed usage is reduced as well as estimated feed cost per day, with some producers reporting an average per day grazing cost of $0.13 per gestating cow.  Many producers recognize the cost control potential of cornstalk grazing but are concerned about maintaining cow condition scores during the second and third trimester of pregnancy.

Programmatic Response: 

Funding from the Leopold Center for Sustainable Agriculture and the Iowa Beef Center provided the opportunity to conduct a cornstalk grazing demonstration in Mahaska County in Iowa.  The purpose of this demonstration was to compare continuous corn residue grazing without grain/co-product supplementation to strip-grazed cornstalks with Distillers Dry Grain (DDG) supplementation.  The treatment group—30 spring calving Angus-based cows—was provided approximately 10 acres of cornstalks each week for seven weeks (49 days).  Dakota Gold Bran was provided at 5-6# per head per day from day 17 through day 49.  The control group—30 spring calving Angus-based cows—was provided 60+ acres of cornstalks without grain or co-product supplementation.   Both the control and treatment groups were fed grass-legume hay for 12 of the 49 test days due to ice conditions.  Body condition scores were evaluated at the beginning and end of the demonstration.

Outcome Statement:  Why is this demonstration important to Iowa cow-calf producers?  1) The treatment group receiving the DDG supplementation in the strip-grazed system maintained their BCS of 5.7 even with three ice events that impacted feed availability for 12 of the 49 days.  During this same period, the BCS of the control cows decreased from a beginning score of 5.7 to 5.4 during the seven week demonstration.  2) The DDG supplemented system was more cost-competitive ($18.82 per head advantage) than the continuous grazed control group.  This difference compares the DDG and hay supplementation costs of the treatment group to the control group’s actual hay and estimated DDG cost to increase the control cow’s BCS by 0.3 points.  3) The demonstration also reflects how non-fenced corn fields can be successfully grazed by utilizing electric fences. 

The results of the demonstration will be summarized and distributed through the Leopold Center of Sustainable Agriculture system and via an Iowa Beef Center fact sheet.  Also, a powerpoint slide presentation is being developed that ISU Extension Beef Field Specialists can use in their educational programs throughout the state.  Through this effort, cow-calf producers can more efficiently utilize their feed resources, reduce winter stored feed costs, and maintain cow body condition through a variety of weather conditions.


140  Iowa Beef Center

Page last updated: April 18, 2009
Page maintained by Linda Schultz,