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A note on the reproductive activity of Hampshire and Suffolk ewes outside the breeding season

Published online by Cambridge University Press:  02 September 2010

L. L. Bellinger  and
V. E. Mendel
L. L. Bellinger
Affiliation:
Department of Animal Science, University of California, Davis 95616, USA
V. E. Mendel
Affiliation:
Department of Animal Science, University of California, Davis 95616, USA
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Summary

The present study investigated the intensity of the anoestrous period in 36 Hampshire and Suffolk ewes as influenced by the photoperiod and the presence of the ram. The study began on 4 April and terminated on 11 June. Ewes kept under natural light in the absence of the ram (Group I) exhibited a limited amount of ovarian activity as determined by cervical smear. Ewes kept under natural light, but in the presence of a ram (Group II) showed an increased amount of cycling (P < 0·05) when compared to that in Group I. Two ewes from Group II mated during the so-called anoestrous period and subse-quently lambed. Ten of 12 ewes, subjected to a decreased photoperiod (Group HI), increased ovarian activity within a few days of light reduction. Five ewes in this group lambed.

Type
Research Article
Information
Animal Production , Volume 19 , Issue 1 , August 1974 , pp. 123 - 126
Copyright
Copyright © British Society of Animal Science 1974

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References

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