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The long-term suppression of heat in cattle with implants of melengestrol acetate

Published online by Cambridge University Press:  02 September 2010

J. F. Roche  and
J. P. Crowley
J. F. Roche
Affiliation:
The Agricultural Institute, Grange, Dunsany, Co. Meath, Ireland
J. P. Crowley
Affiliation:
The Agricultural Institute, Grange, Dunsany, Co. Meath, Ireland
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Summary

The effectiveness of silastic rubber implants impregnated with melengestrol acetate (MGA) to suppress heat in heifers being finished for beef was tested. Nine uniparous females received MGA implants, nine received 0·5 mg MGA orally and eight similar non-treated animals served as controls for a 110-day experimental period. Based on occurrence ofheat and ovarian examination during treatment and at slaughter, the silastic implants were effective in suppressing heat throughout the experimental period. The animals with implants also had a significantly higher rate of daily gain than the controls (P<0·1). In a second experiment the implants were effective in suppressing heat but the increase in daily gain did not reach significance. Silastic implants of MGA are effective for the long-term suppression of oestrus in finishing heifers and their effective life span is sufficiently long for use under commercial farming conditions.

Type
Research Article
Information
Animal Production , Volume 16 , Issue 3 , June 1973 , pp. 245 - 250
Copyright
Copyright © British Society of Animal Science 1973

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References

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