Abstract
Growth rate, feed efficiency, and feed consumption were significantly increased by stilbestrol pellet implantation. Spaying of heifers for the feedlot resulted in decreased rate of gain and decreased feed efficiency. No benefit was derived in the feedlot as a result of spaying. Treatment of heifers with testosterone propionate appeared to stimulate growth, but the effect was of short duration for dosage levels used. Feeding thiouracil, 4 gm. per heifer per day, did not noticeably affect growth rate, feed consumption, or feed efficiency. Feeding thyroprotein at a level of 0.5 gm. per 100 pounds body weight per day decreased rate of gain and feed efficiency. Erythrocyte counts were decreased as a result of stilbestrol treatments and increased as a result of thiouracil treatment. The differences were significant. None of the treatments employed significantly affected blood cholesterol levels of beef heifers. Spaying significantly increased the blood lipid content. Copyright © . .