Skip to main content Accessibility help
×
Home

The effects of single injections of progesterone on oestrous cycle length in ewes

  • I. W. Dixon (a1) and C. J. Thwaites

Summary

Two hundred and forty mature Merino ewes were used in a factorial experiment to investigate the effects of single injections of either 0, 40, 80 or 160 mg progesterone on the length of the subsequent oestrous cycle. Equal numbers of ewes (15 per group) received subcutaneous and intramuscular injections, and equal numbers were treated either on the day of oestrus or the following day.

Oestrous cycle length was significantly reduced in all treated groups, with a minimum cycle length of 7–10 days following treatment with 80 or 160 mg progesterone. Neither route of administration nor day of treatment significantly affected the response. The conception rate achieved by treated ewes at the first post-treatment oestrus did not differ significantly from that in comparable controls.

The results suggest that a single massive dose of progesterone on the day of oestrus is an effective means of shortening the oestrous cycle of the ewe without loss of fertility.

Copyright

References

Hide All
Lewis, P. E., Taylor, W. C. & Inskeep, E. K. (1968). Exogenous progesterone on ovine corpora lutea. J. Anim. Sci. 27, 1193.
Robinson, T. J. (1964). Synchronization of oestrus in sheep by intravaginal and subcutaneous application of progestin impregnated sponges. Proc. Aust. Soc. Anim. Prod. 5, 4752.
Thwaites, C. J. (1971). Exogenous progesterone and oestrous cycle length in the ewe. J. agric. Sci., Camb. 77, 147–9.

The effects of single injections of progesterone on oestrous cycle length in ewes

  • I. W. Dixon (a1) and C. J. Thwaites

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed