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The effect of constant long daily photoperiod upon the onset of puberty in ewes

Published online by Cambridge University Press:  27 March 2009

I. D. Smith
Affiliation:
University of Queensland, Brisbane, Australia

Extract

The effect upon the onset of reproductive activity of exposure of ewe lambs of three British breeds (Border Leicester, Southdown, Suffolk) to constant long daylight hours (16 h light/8 h dark) was studied.

Oestrus, ovulation and conception were depressed but not inhibited; however, only the incidence of conception was significantly less than in the control group. Athough the treatment retarded the onset of oestrous activity, the age at first oestrus was still within the normal age range for puberty.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1967

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