Purdue University Agricultural Experiment Station Lafayette, Indiana
Mimeo A.H. 149 April 29, 1955 (A Progress Report)
The Effect of Feeding Three Female Hormone-Like Materials to Feeder Calves
F. N. Andrews, Martin Stob, T. W. Perry and W. M. Beeson Department of Animal Husbandry
The majority of research conducted to determine the effect of implanting or feeding hormone-like materials to beef cattle has involved heifers and steers that were past 1 year of age at the time of the start of the trial. Although it is reasonable to believe the same effect would be obtained when feeder calves (less than 1 year of age) were used, it was desirable to set a trial to study:
a.	the effect of orally administered female hormone-like substances on the feedlot and packing plant performance of steer and heifer calves,
b.	the comparative effect of three different substances -diethylstilbestrol, dienestrol and hexestrol, and,
c.	as a side study, four open gilts were placed in each of the pens of steers and heifers to determine whether sufficient hormone or hormone residue was coming through the cattle to have an effect on open gilts following them.
Expe rimental
Thirty-five Shorthorn steer and heifer calves were divided into four groups on the basis of sex, liveweight and apparent thrift. The four lots were penned in drylot and were fed a fattening ration of shelled corn-full fed, Purdue Supplement A-2.0 pounds, hay, silage and minerals.
Lot I served as the control and received no hormone. Lot II was fed 10 milligrams of stilbestrol per steer per day, Lot III was fed 10 milligrams of dienestrol and Lot IV was fed 10 milligrams hexestrol. The respective hormones were dissolved in corn oil and mixed into the supplement.
Four open gilts were included in each lot to determine whether fecal hormone or hormone residue was present in sufficient quantities to have an effect on the swine following hormone-fed cattle.
Re suit s
Steers and heifers receiving 10 milligrams of stilbestrol Per animal daily, in addition to a typical dry lot fattening ration, gained 20 percent more rapidly than similar animals receiving no hormone in their ration (2.84 lb. per day vs. 2.37 lb. per day).