Purdue University-Agricultural Experiment Station Lafayette, Indiana
Mlmeo AS-253 April 24, 1959 (Progress Report)
THE EFFECT OF CERTAIN MALE AND FEMALE HORMONAL SUBSTANCES ON GAIN, FEED EFFICIENCY AND CARCASS QUALITY OF FATTENING HEIFERS
F. N. Andrews, W. M. Beeson, Martin Stob, T. W. Perry and M. T. Mohler
Department of Animal Science
Purdue studies with beef heifers carried out in 1947 and 1948 showed that the implantation of 42 or 43 milligrams of diethylstilbestrol pellets increased rate of gain and improved feed efficiency. Several objectionable effects were observed; mammary stimulation, relaxation of the lumbar region and raising of the tailhead, and swelling of the vulva. In some heifers implanted with 60 milligrams or more of diethylstilbestrol while on pasture the undesirable effects were even more pronounced.
Since 1947, it has been shown that the implantation of 12, 24 or 36 milligrams of diethylstilbestrol or 24 or 36 milligrams of hexestrol will improve gain and feed efficiency of heifers in dry lot. It has also been shown that the daily feeding of 6, 10, or 12 milligrams of diethylstilbestrol will increase rate of gain and feed efficiency in heifers.
In general, experiments throughout the United States in which beef heifers have been implanted with estrogens such as diethylstilbestrol, hexestrol or estradiol, or have been fed diethylstilbestrol, the increases in gain and feed efficiency have not been as great as in steers. In addition, the possibility that excessive stimulation of the reproductive organs may lead to uterine or vaginal prolapse is always present. As reported at the 1957 Purdue Cattle Feeders Day, 8 of 24 heifers implanted with 24 or 36 milligrams of diethylstilbestrol had vaginal prolapse and 3 were sold before the feeding period ended.
Because of interest in making the gains and feed efficiency of beef heifers comparable with steers, and because of the need to develop effective and safe hormonal treatments for heifers, it was decided to compare.*
1.	Stilbestrol Implantation alone and in combination with four male hormonal substances.
2.	Combinations of the natural estrogen, estradiol, with male hormone and progresterone.
The diethylstilbestrol and testosterone propionate pellets were furnished by Chas. Pfizer & Co., the fluoxymesterone and 11 betahydroxy-17-alpha-methyItestosterone by the Upjohn Co., and the estradiol-progesterone pellets and the injectable paste by E. R. Squibb & Sons.