Abstract
Eighteen steers were paired and randomly assigned to either a control ration or a ration containing 10 mg. of stilbestrol per steer daily. The rations were fed in equal quantities to both lots as determined by the group which consumed the least feed. Average length of the feeding period was 193 days. Steers receiving stilbestrol gained faster and were more efficient in feed conversion. Carcass grades and yields were essentially equal. Other than a significant increase in chest depth, various carcass measurements were not statistically different. Visual comparison of photographs of the 12 th rib cut and percent ether extract of the rib-eye muscles showed less marbling in rib eyes from treated cattle. No difference was found in the area of the rib eyes or fat thickness covering the rib eye. The 9–11 rib sections from stilbestrol-fed cattle contained less extract and more water, protein and ash. The higher amount of protein and ash in the bones of treated steers was a major contributing factor in the protein and ash of the reconstituted 9–11 ribs. Estimations of body composition based on either 9–11 rib analysis data or antipyrine data were in close agreement. Copyright © . .