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Rate of gain, efficiency of feed conversion, physiological effects and certain carcass measures are reported for three lots of steers treated as follows: Lot I, control; Lot II, fed diethylstilbestrol (10 mg. per head daily); Lot III, implanted with combination progesterone-estradiol pellets (1.5 gin. progesterone and 50 mg. estradiol).Implanted steers had a significantly greater daily rate of gain than either stilbestrol-fed cattle or controls. Stilbestrol-fed steers had a significantly higher daily rate of gain than the controls. Average daily gains were 2.30, 2.64, and 3.03 lb., respectively, for the control, stilbestrol-fed and implanted steers. Implanted cattle ate an average of 16.0 lb. of corn per day, stilbestrol-fed steers 15.3 lb. and control steers 14.8 lb., indicating an increased appetite from hormone stimulation.There were no significant differences in dressing percentage, cooler shrink, heart, liver, spleen or hide. There were no significant differences in carcass grade. As estimated by the 9-10-11 rib cut (Hankins, 1946), carcasses from implanted steers had a significantly greater proportion of separable lean, and significantly lower proportion of separable fat than the carcasses for either stilbestrol-fed or control groups.Moisture of external fat, internal fat, Longissimus dorsi, and combined separable fat and lean was not significantly different between groups. No significant differences were found in percentage of ether extract of Longissimus dorsi, or of combined separable fat and lean.There was no difference in cooking shrink or in Warner-Bratzler shear readings.Adrenal glands appeared normal in all groups. Hormone treatment either by implantation or feeding resulted in an increased diameter of the prostatic portion of the urogenital tract and an increase in size of the bulbourethral glands and seminal vesicles, indicating physiological activity due to both hormone treatments. There was some evidence of secretory activity in the prostrate and bulbourethral glands of treated steers. There was no evidence of desquamation or keratinization of epithelium and no evidence of carcinogenesis in any tissues examined.

In a feeding trial involving fifty 75-lb. lambs, a 7.13 percent crude protein basal ration was fed. Adding either urea, biuret or crude biuret, or replacing part of the corn with soybean oil meal, significantly increased the average daily gain and feed efficiency of the lambs. No significant differences were noted among the lots fed the various supplemental nitrogen sources.It is concluded that, under the conditions of this experiment, urea, biuret and crude biuret are satisfactory sources of supplemental nitrogen for growing-fattening lambs. In addition, biuret appears to be less toxic than urea when fed in large amounts.

The effect of three different levels of carotene intake, supplied by alfalfa hay, upon the carotene and vitamin A concentration of the blood and milk of Hereford cows and the blood of their calves is reported.Plasma carotene levels were positively correlated with carotene intake. No consistent differences in plasma vitamin A could be attributed to ration. Both plasma carotene and vitamin A declined at or shortly after parturition and then rose during the subsequent 30 days. The plasma carotene and vitamin A level of the calves increased rapidly during the first few days and then decreased to a level which was generally maintained throughout the first month of life.Despite the relatively low blood plasma levels of carotene and vitamin A observed during this study all the cows produced normal calves and raised them successfully. It is suggested that seasonal declines of plasma vitamin A and carotene may occur for short periods of time without the appearance of clinical symptoms of avitaminosis.