Mimeo No. A.H. 60 Dept. of Animal Husbandry
April 27, 1951 (2M)
EFFECT OF HORMONES ON THE GROWTH AND FATTENING OF YEARLING STEERS. Exp. II.
F. N. Andrews, W. M. Beeson and F. D. Johnson Purdue University, Lafayette, Indiana
Studies at Purdue during the past decade have shown that hormones such as stilbestrol may, under certain conditions, increase growth and fattening and improve feed efficiency in cattle. (A.H. Mimeos. 37 and 46.)
On November 15, 1950, four groups of 10 yearling steers each were started on a fattening ration composed of corn-and-cob meal, cottonseed meal, molasses feed, clover-timothy hay, bonemeal and salt. The steers were kept on full feed until the close of the experiment on April 14, 1951, a period of 140 days. In one group 60 milligrams of stilbestrol pellets were placed beneath the skin in the neck, a second group received 120 milligrams of stilbestrol pellets and a third group was treated with 80 milligrams of dienestrol.
The data are summarized in Table I.
Summary
The steers which received 120 milligrams of stilbestrol gained an average of 541b. more than the controls and required 85 lb. less concentrates per 100 lb. of gain. The cattle which received 60 mg. of stilbestrol or 80 mg. of dienestrol gained 47 lb. more than the controls and required approximately 85 lb. less concentrate per 100 lb. of gain. Most of the hormone treated steers showed an elevation of the tail head during the early part of the experiment. This tended to decrease with time but it was still very evident in some of the cattle at the end of the trial. This detracts from the appearance of the animals.
In previous experiments and in this one, the carcass grades of the treated animals have been lower than those of the controls. However, the dienestrol group compares very favorably with the controls.