Alternative Rations for Maintaining Pregnant Beef Cows

William L. Shockey, Ph.D.
Extension Agent, Preston County
Agriculture, Natural Resources, and Community Development
West Virginia University Extension Service
9/99

Drought situations leave many feeder calf producers with reduced stocks of homegrown hay. Losses of 40% to 70% of normal forage production are often reported. Under normal conditions, pregnant beef cows are fed hay during the winter to maintain them until they calve in the spring. A 1,000-pound pregnant beef cow requires a ration that contains about 8% crude protein (CP) and 54% total digestible nutrients (TDN). Timothy hay cut at the full-head growth stage, for example, contains 8.5% CP and 57% TDN.

Many alternative feedstuffs have been suggested to supplement reduced forage stocks. What follows are several rations that make use of some alternative feeds. These rations are designed to maintain a mature 1,000-pound pregnant beef cow, and each ration contains a minimum of 8.5% CP and 54% TDN. When drought conditions do not limit hay stocks, most brood cows consume about 16 pounds of grass hay plus small amounts of mineral and salt. The following rations would also require mineral and salt supplementation.

Ration 1

INGREDIENT

POUNDS

Grass Hay

4

Corn Stover

8

Corn/Urea Mix*

4

Total

16

*Corn/Urea Mix contains 3.9 pounds corn and .1 pound urea UREA

Ration 2.

INGREDIENT

POUNDS

Grass Hay

6

Oat Straw

6

Corn/Urea Mix*

4

Total

16

*Corn/Urea Mix contains 3.9 pounds corn and .1 pound urea UREA

Ration 3.

INGREDIENT

POUNDS

Grass Hay

6

Oat Straw

7

Whole Cottonseed

3

Total

16

Ration 4.

INGREDIENT

POUNDS

Grass Hay

4

Soybean Hulls

8

Corn

4

Total

16

Successful feeding of roughage extender and by-product feeds depends on proper ration balancing. Do not attempt to incorporate by-products or other alternative forage sources until you obtain a nutrient analysis from a laboratory. After obtaining this analysis, use proper ration balancing techniques to incorporate these feedstuffs into the overall ration. If you decide to use by-products, don't wait until your home-grown forage sources are exhausted before incorporating them into your rations. Again, they should be fed as a roughage extender, not as a total roughage replacement. For sources of analytical laboratories and ration balancing expertise, contact your county Extension office.

Drought-stressed corn silage

Because of the drought, much corn silage is being harvested that contains few, if any, ears of corn. Nutrient analysis of this material shows a CP percentage that is higher and a TDN percentage that is lower than "normal" corn silage. Some lab analyses of "earless" corn silage have averaged 11% CP and 64% TDN. As a point of reference, "normal" corn silage is 8.5% CP and 70% TDN.

"Earless" corn silage can be supplemented with shelled corn to create a mixture that approximates the nutrient composition of "normal" corn silage. The supplementation should be at a rate of 80 parts "earless" corn silage to 20 parts shelled corn on a dry matter basis. For example, if your "earless" corn silage is 40% dry matter, then the as-fed rate of supplementation would be 10 parts "earless" corn silage to 1 part shelled corn.

It may not be necessary to supplement drought-stressed corn silage with shelled corn. Before making that decision, determine the nutrient requirements of the animals that are going to be fed the silage. If the "earless" corn silage provides enough energy to meet the animal’s needs, then supplementation is not necessary. Otherwise, as stated above, supplement at a ratio of 80/20 on a dry matter basis to provide an adequate forage.