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The influence of nutrition on reproduction in the ewe 2. Effects of undernutrition on pituitary responsiveness to luteinizing hormone-releasing hormone stimulation

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 ewes in good body condition at the start of the breeding season were given either sufficient feed to maintain their body weight or 500 g/kg of a maintenance ration such that they showed a continuous fall in body weight. On three separate occasions after introducing the nutritional regimens, all ewes were challenged on day 12 of the oestrous cycle with 150 μg luteinizing hormone-releasing hormone. Prolonged chronic undernutrition resulted in a significant increase in luteinizing hormone release in response to luteinizing hormone-releasing hormone injection (P < 0·05), whereas the mean pre-injection luteinizing hormone concentrations were significantly reduced by undernutrition (P < 0·01).

Type
Research Article
Information
Animal Production , Volume 32 , Issue 3 , June 1981 , pp. 257 - 260
Copyright
Copyright © British Society of Animal Science 1981

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References

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