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The reproductive performance of Border Leicester ewes in contrasting photoperiodic environments

Published online by Cambridge University Press:  27 March 2009

H. Ll. Williams  and
C. J. Thwaites
H. Ll. Williams
Affiliation:
Department of Livestock Production, University of New England, Armidale, New South Wales, Australia, 2351
C. J. Thwaites
Affiliation:
Department of Livestock Production, University of New England, Armidale, New South Wales, Australia, 2351
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Summary

Border Leicester ewes were kept in three contrasting photoperiodic environments, the rhythm at latitude 30° 32′ S (group 1) - 12 h light: 12 h dark interrupted by 6 weeks of continuous light (group 2a) and 12 h light: 12 h dark (group 2b) - from August 1972 to September 1973. In group 1 all ewes exhibited oestrus compared with 87·5% and 57·1% in groups 2(a) and 2(b) respectively. The mean number of oestrous periods per ewe ranged from 4·4 in group 1 to 3·0 in group 2(a) and 1·0 in group 2(b). It is concluded that the non-fluctuating light rhythm had an adverse effect on the reproductive potential of the treated groups and that Border Leicester ewes are dependent on a fluctuating light rhythm for normal reproductive function.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 83 , Issue 1 , August 1974 , pp. 101 - 104
Copyright
Copyright © Cambridge University Press 1974

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References

REFERENCES

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