Research Progress Report 91
January. 1964
Effect of Low and High Coumestrol Dehydrated Alfalfa Meal and Double Stilbestrol Treatment [Implant and Oral] on the Gain and Feed Efficiency of Steer Calves
Martin Stob, W. M. Beeson, T. W. Perry, M. T. Mohler and R. B. Harrington, Department of Animal Sciences
Summary
Daily gains of steers fed dehydrated alfalfa pellets containing a high level of coumestrol were not significantly different from those of steers fed pellets containing a low level of coumestrol.
Implantation of steers with 36 mg of stilbestrol significantly increased daily gains compared to steers not implanted, irrespective of level of coumestrol fed.
Neither 5 nor 10 mg. orally administered stilbestrol significantly increased daily gain of steer calves.
Simultaneous treatment of steers with oral and implanted stilbestrol did not improve gains over those produced by oral feeding or implantation separately.
Neither stilbestrol administration nor level of fed coumestrol signigicantly affected carcass grade of steer calves.
Estrogenic residues were not detected in the fresh or dried livers of steer calves fed low or high coumestrol dehydrated alfalfa and 10 mg orally administered, 36 mg im-
planted or a combination of 10 mg oral and 36 mg implanted stilbestrol.
Previous Research
Female sex hormones improve growth rate and feed efficiency of cattle. These desirable effects are produced with several levels and various routes of hormone administration and under many types of management. The present recommended levels of either 36 mg implantation or 10 mg daily oral feeding of stilbestrol are generally thought to represent optimal dosages for cattle fattened in dry lot. Implantation with 24 mg stilbestrol is usually sufficient to stimulate growth of cattle fattened on pasture because of the supplementary hormone thought to be present in forages.
Recently published research suggests that the commonly employed dosages of stilbestrol for cattle could be modified to promote even more rapid rate of gain. Other work indicates dehydrated alfalfa meal contains a factor or factors which stimulate growth in cattle and that perhaps this factor is coumestrol, a newly discovered estrogen found in legumes.
1/ This research supported in part by a research grant from American Dehydrators Association, Kansas City, Missouri.
PURDUE UNIVERSITY • Agricultural Experiment Station • Lafayette, Indiana