Research Progress Report 291 Project 1295 March, 1967
Grain Supplementation of Spring-calving Beef Cows on Tall Fescue Winter Pasture and Round Bales
L. L. Wilson, R. Peterson, Jr., M. E. Heath, C. J. Callahan, C. J. Kaiser and K. Hawkins
Departments of Animal Sciences and Agronomy

One of the primary methods for wintering a beef cow herd in Southern Indiana is to mow the spring growth of tall fescue (Festuca arundinocea Schreb.), bale with a round baler, and leave the bales in the field. The round bales and the tall fescue regrowth are grazed by the cow herd during the winter.

Tall fescue seems to offer the greatest usefulness for fall, winter and early spring grazing. Although the winter grazing method outlined above has been used successfully many times -- particularly if strip-grazed — little is known about the nutritional limitations of this system. In 1964, a trial was conducted at the Forage Farm in which half of a cow group received one pound of corn in addition to winter fescue pasture and protein supplement. Brood cows which received one additional pound of corn lost 27 pounds less weight during the wintering period but the calves from the cows which received additional grain gained 0.22 pounds per day slower. These earlier results, observed when only one pound of corn was used, prompted repeating the trial with a higher level of grain supplementation.

Experimental Procedure

Cattle were removed from field 5 (25 acres) on April 15, 1965. The fescue seed
was combined and the aftermath round-baled on about July 28, 1965. The field was split into two 12.5-acre plots and the number of bales were equalized on the two plots. Each plot was further divided into four sections with an electric fence for strip-grazing.

Forty brood cows were randomly allotted (considering cow weight, age, and sire of unborn calf) to two treatments:

Lot # 1 (east side of field 5) to receive a daily ration of 0.4 pound of soybean oil meal plus 3.0 pounds of ground shelled corn.

Lot # 2 (west side of field 5) to receive a daily ration of 0.9 pound of soybean oil meal and 0.1 pound of ground shelled corn.

Sufficient synthetic vitamin A was added to the concentrates to provide 22, 000 I.U. per head daily for both lots.

Each lot had access to two mineral boxes; one containing trace-mineralized salt and the other a 2:1 ratio of steamed bone meal to trace-mineralized salt.

The above concentrate rations were figured so as to allow comparable protein content but represent a difference of about 1.9 pounds in total digestible nutrients (TDN)

PURDUE UNIVERSITY • Agricultural Experiment Station • Lafayette, Indiana