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The influence of nutrition on reproduction in the ewe 1. Effects on ovulation rate, follicle development and luteinizing hormone release

Published online by Cambridge University Press:  02 September 2010

W. Haresign
W. Haresign
Affiliation:
Department of Agriculture and Horticulture, University of Nottingham School of Agriculture, Sutton Bonington, Loughborough, Leicestershire LE12 5RD
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Abstract

Two groups of 15 ewes in store body condition were either given a maintenance level of feeding or a twice-maintenance level (flushed) during the course of one oestrous cycle. Five ewes from each feeding level were slaughtered at 0, 18 or 48 h after the onset of the oestrus at the end of the treatment period and measurements were made of the luteinizing hormone content of their pituitary, the luteinizing hormone concentration in their blood plasma, their ovulation rates, and ovarian follicle numbers and sizes.

‘Flushed’ ewes had a significantly higher ovulation rate (260, s.e. 0·24 v. 1·80, s.e. 0·20; P <0·05), although there was no significant difference in either pituitary luteinizing hormone content or plasma luteinizing hormone concentrations at oestrus.

Analysis of the patterns of ovarian follicle distribution suggest that flushing ewes for one oestrous cycle might increase ovulation rate by preventing the late atresia of large follicles in the last 30 h before ovulation.

Type
Research Article
Information
Animal Production , Volume 32 , Issue 2 , April 1981 , pp. 197 - 202
Copyright
Copyright © British Society of Animal Science 1981

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References

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