Saving Hay by Limit Feeding Corn

The lack of forage due to drought and current hay prices have producers considering alternative options for feeding cows this winter. One option we might consider is replacing some hay in the diet with corn.

Erin Laborie, Nebraska Beef Systems Educator shared some thoughts in a recent BeefWatch article. Since corn has a higher energy content than hay, the cost of feeding hay is often higher than corn on a price per pound of energy basis. For example, corn priced at $6.76/bushel ($241/ton) with a total digestible nutrients (TDN) value of 88% equates to approximately $0.16 per pound of TDN while hay priced at $205/ton with a TDN value of 52% is nearly $0.22 per pound of TDN.  If you need to compare other feeds, the UNL Feed Cost Cow-Q-Lator is a great resource for comparing feedstuffs on a per pound of energy or protein basis.

While hay can be offered free choice due to its low energy content, high energy feeds like corn should be limit fed to avoid putting too much condition on cows. Corn is relatively low in protein, so providing a 30-40% protein supplement can help meet the cow’s protein requirement. We can also consider a non-protein N source as the added dietary starch allows for full utilization. Additionally, there must be some forage (0.25-0.5% of body weight on a dry matter basis) included in grain-based diets to promote rumen function and prevent digestive upsets. 

While corn can be used as a supplement in a primary hay diet (no more than 2-3 lb. whole corn per day), we should recognize that this approach brings some inefficiencies into the system.  Microbes in the rumen change depending on diet.  Those that use the fiber in a hay diet are not the same as those that digest the starch in corn.  As such, any diet that is in the middle lowers the amount of energy we can expect from corn in the ration from 88% to 83%. 

When utilizing a limit fed, grain-based diet, there are several factors producers should take into consideration to help facilitate the success of the program:

  • Adjust cows to the limit fed diet over a week to ten-day period by gradually increasing the corn and reducing the hay to desired levels. This will help cows transition to the new ration and minimize digestive upsets.
  • Provide at least 24 to 30 inches of bunk space per cow. Adequate space is needed to ensure that all cows have an opportunity to eat the limited feed that will be provided.
  • Utilize an ionophore to improve feed efficiency and help minimize digestive upsets.  Ensure that the one you choose is labeled for cows.
  • Divide cows into groups based on age and pecking order, if possible, so that boss cows do not keep younger and more timid cows from getting their share of the ration.
  • Realize that cows will act hungry when receiving a limit fed diet, even though the ration is meeting the nutrient needs of the cow.
  • Feed cows at a consistent time each day to help minimize cows displaying discontented behavior.
  • Adjust the ration for changes in the cow’s nutrient requirements as needed. The nutrient needs of the cow are highest during late gestation and early lactation. Additionally, cold weather events can increase the energy requirements of the cow.

High hay prices and low supply may mean getting creative with cow diets.  Corn can be used as an energy source, but needs to be priced out and a ration developed appropriately to avoid digestive issues and to get the full benefit in a diet.

-Ben Beckman is a beef systems Extension Educator serving the counties of Antelope, Cedar, Knox, Madison and Pierce.  He is based out of the Cedar County Extension office in Hartington.  You can reach him by phone: (402) 254-6821 or email: