Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-27T22:40:32.066Z Has data issue: false hasContentIssue false
  • English
  • Français

A note on the relationship between undernutrition and luteinizing hormone release in the ewe

Published online by Cambridge University Press:  02 September 2010

Alison D. Crump ,
R. G. Rodway  and
M. A. Lomax
Alison D. Crump
Affiliation:
Department of Animal Physiology and Nutrition, University of Leeds, Leeds LS2 9JT
R. G. Rodway
Affiliation:
Department of Animal Physiology and Nutrition, University of Leeds, Leeds LS2 9JT
M. A. Lomax
Affiliation:
Department of Animal Physiology and Nutrition, University of Leeds, Leeds LS2 9JT
Get access

Abstract

The effects of a moderate level of undernutrition on the release of luteinizing hormone (LH) at oestrus and after luteinizing hormone releasing hormone (LHRH) treatment was investigated. Plasma levels of glucose, non-esterified fatty acids (NEFA), cortisol and prolactin were also investigated.

During the early breeding season 10 mature ewes were placed on either a maintenance (M) or a restricted (R) diet. After 50 days of dietary treatment their oestrous cycles were synchronized and blood samples were taken over the oestrous period. Eight days later LHRH was administered and blood samples were taken for the following 6 h.

After 50 days of treatment mean body- weights were 66 (s.e. 4) and 53 (s.e. 3) kg, and mean body condition scores were 3·5 and 2·0 for the M and R groups respectively. The pre-ovulatory and LHRHinduced LH peaks were similar in both groups as were the prolactin profiles. However, plasma NEFA levels were elevated and glucose and cortisol levels were reduced in the restricted group.

It is concluded that the reduction in energy intake achieved in this experiment, although sufficient to cause significant metabolic changes had no effect on the release of LH either at oestrus or after LHRH treatment.

Type
Research Article
Information
Animal Production , Volume 40 , Issue 2 , April 1985 , pp. 359 - 361
Copyright
Copyright © British Society of Animal Science 1985

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: 69–79CrossRefGoogle Scholar
Crump, A. D., Lomax, M. A. and Rodway, R. G. 1982. Oestradiol-induced luteinizing hormone (LH) release is inhibited by 2-deoxy-D-glucose infusion in sheep. J. Physiol, Land. 330: 93P–94P (Abstr.).Google Scholar
Gunn, R. G. and Doney, J. M. 1975. The interaction of nutrition and body condition at mating on ovulation rate and early embryo mortality in Scottish Blackface ewes. J. agric. Sci., Camb. 85: 465–470.CrossRefGoogle Scholar
Haresign, W. 1981. The influence of nutrition on reproduction in the ewe. 2. Effects of undernutrition on pituitary responsiveness to luteinizing hormone-releasing hormone stimulation. Anim. Prod. 32: 257–260.Google Scholar
Lishman, A. W., Allison, S. M. J., Fogwell, R. I., Butcher, R. L. and Inskeep, E. K. 1979. Follicular development and function of induced corpora lutea in underfed postpartum anoestrous beef cows. J. Anim. Sci. 48: 867–875.CrossRefGoogle Scholar
Lishman, A. W., Stielau, W. J., Dreosti, I. E., Botha, W. A., Stewart, A. M. and Swart, C. E. 1974. The release of LH at oestrus in ewes on planes of nutrition during lactation. J. Reprod. Fert. 41: 227–230.CrossRefGoogle ScholarPubMed
McClure, T. J. 1970. An experimental study of the causes of a nutritional and lactational stress infertility of pasture-fed cows, associated with a loss of bodyweight at about the time of mating. Res. Vet. Sci. 11: 247–254.CrossRefGoogle ScholarPubMed
Moberg, G. P., Watson, J. G., Stoebel, D. P. and Cook, R. 1981. Effect of cortisol and dexamethazone on the oestrogen-induced release of luteinising hormone in the anoestrous ewe. J. Endocr. 90: 221–225.Google Scholar
Reid, I. M., Roberts, C. J., Collins, R. A. and Dew, Sally M. 1979. Fatty liver and infertility in dairy cows in early lactation. Proc. Nutr. Soc. 38: 67A (Abstr.).Google ScholarPubMed