Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-23T05:37:11.894Z Has data issue: false hasContentIssue false
  • English
  • Français

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
Get access

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

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Allen, D. M. and Lamming, G. E. 1961. Nutrition and reproduction in the ewe. J. agric. Sci., Camb. 56: 69–79.CrossRefGoogle Scholar
Arimura, A. and Schally, A. V. 1971. Augmentation of pituitary responsiveness to LH-releasing hormone (LH-RH) by estrogen. Proc. Soc. exp. Biol. Med. 136: 290–293.CrossRefGoogle ScholarPubMed
Coop, I. E. 1966. Effect of flushing on reproductive performance of ewes. J. agric. Sci., Camb. 67: 305–323.CrossRefGoogle Scholar
Foster, J. P. and Crighton, D. B. 1974. Luteinizing hormone (LH) release after single injections of a synthetic LH-releasing hormone (LH-RH) in the ewe at three different reproductive stages and comparison with natural LH release at estrus. Theriogenology 2: 87–100.CrossRefGoogle Scholar
Gunn, R. G. and Doney, J. M. 1979. Fertility in Cheviot ewes. 1. The effect of body condition at mating on ovulation rate and early embryo mortality in North and South Country Cheviot ewes. Anim. Prod. 29: 11–16.Google Scholar
Gunn, R. G., Doney, J. M. and Smith, W. F. 1979. Fertility in Cheviot ewes. 3. The effect of level of nutrition before and after mating on ovulation rate and early embryo mortality in South Country Cheviot ewes in moderate condition at mating. Anim. Prod. 29: 25–31.Google Scholar
Haresign, W. 1981. The influence of nutrition on reproduction in the ewe. 1. Effects on ovulation rate, follicle development and luteinizing hormone release. Anim. Prod. 32: 197–202.Google Scholar
Haresign, W. and Lamming, G. E. 1978. Comparison of LH release and luteal function in cyclic and LH-RH-treated anoestrous ewes pretreated with PMSG or oestrogen. J. Reprod. Fert. 52: 349–353.CrossRefGoogle ScholarPubMed
Lamming, G. E. 1971. Plane of nutrition and reproduction in the ruminant. In Proc. Univ. Nott. Nutr. Conf. Feed Mfrs, No. 5 (ed. Swan, H. and Lewis, D.), pp. 2–15. Churchill Livingstone, London.Google Scholar
Matsuo, J., Baba, Y., Nair, R. M. G., Arimura, A. and Schally, A. V. 1971. Structure of the porcine LH- and FSH-releasing hormone. 1. The proposed amino acid sequence. Biochem. biophys. Res. Commun. 43: 1334–1339.CrossRefGoogle Scholar
Mulinos, M. G. and Pomerantz, L. 1940. Pseudohypophysectomy: a condition resembling hypophysectomy produced by malnutrition. J. Nutr. 19: 493–504.CrossRefGoogle Scholar
Reeves, J. J., Arimura, A. and Schally, A. V. 1971. Changes in pituitary responsiveness to luteinising hormone-releasing hormone (LH-RH) in anestrous ewes pretreated with estradiol benzoate. Biol. Reprod. 4: 88–92.CrossRefGoogle Scholar