| Material Information
||Our observations with Melengestrol acetate (MGA) for heifers
||2 p. : ; 28 cm.
||Chapman, H. L ( Herbert L. ), 1923-
Range Cattle Experiment Station
||Range Cattle Experiment Station
||Place of Publication:
||Heifers -- Feeding and feeds -- Florida ( lcsh )
Hormones in animal nutrition ( lcsh )
||government publication (state, provincial, terriorial, dependent) ( marcgt )
non-fiction ( marcgt )
||Statement of Responsibility:
||H.L. Chapman, Jr.
||Mimeo report (Range Cattle Experiment Station) ;
| Record Information
||University of Florida
||All rights reserved by the source institution and holding location.
||oclc - 86110536
Mimeo Series RCS 68-4 May!9uLj E LI0 .
OUR OBSERVATIONS WITH IMEENGESTRQL
ACETATE (MGA) FOR HSEIfRS-2/ 16 13
NIAY 18 1968
H. L. Chapman, Jr.-
S.A.S. Uni. of Fior: d
Melengestrol acetate (MGA) is a synthetic female hormbne-that---'--'
number of experiment stations have demonstrated to stimulate rate-of gain and
feed efficiency of feedlot heifers. The majority of earlier reports have
been with English-type heifers. The purpose of this experiment was to
determine if MGA affected growth, feed utilization or carcass characteristics
of crossbred heifers being fattened in drylot and.to determine if
diethylstilbestrol (DES) altered the effect.
Forty-five Brahman-crossbred heifers of approximately 10 months of age,
were divided into three equal groups on the basis of weight and quality and
allotted to the following experimental design:
number Treatment description
2 0.4 mg MGA/head/daily
3 0.4 mg MGA/head/day + 24 mg DES implanted at
the beginning of the experiment.
The experimental ration was comprised of 40% dried citrus pulp, -
27% hominy feed, 10% cottonseed meal (41%), 5% dehydrated' alfalfa
meal (17%), 15% cottonseed hulls, 1% urea-262, 1.5% dicalcium phosphate
and 0.5% trace mineralized salt. Vitamin A was added to the ration at
the level of 1,000 I.U. per pound of feed.
/ Presented at 1968 Beef Cattle Short Course, University of Florida.
SPhysiological studies were made by A. C. Warnick and carcass
evaluations by A. Z. Palmer and J. W. Carpenter.
2/ Grateful acknowledgement is made to TUCO Products Co., Division of
Upjohn Co., Kalamazoo, Michigan for their financial support of this
_/ Animal Nutritionist and Head, Range Cattle Experiment Station.'
At the conclusion of a 151-day feeding period the heifers were
transported to Gainesville for carcass studies. The experimental
results are listed below:
Initial weight (lb)
Final weight (lb)
Total gain (lb)
Daily gain (lb)
Gainesville weight (lb)
Intransit shrink (%)1/
Warm carcass weight (lb)
Chilled carcass weight (lb)
Cooler shrink (%)
Li'ver weight (lb)
Fat over rib-eye (in)
Rib-eye area (sq.in.)
Est. % yield
Right ovary wt. .(m).
Ni. active CL2/
Size largest follicle (mm)
Nop!. .follicles over 5 mm
Left ovary wt. (gm)
No.. active CL
Size largest follicle (mm)
No. follicles over, 5 mm
Uterine weights (gm)
MGA MGA + DES
1/ Intransit distance was 180 miles.
SDressing percent = chilled carcass weight
3/ CL = corpus luteum.
The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University