Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-27T19:00:41.744Z Has data issue: false hasContentIssue false
  • English
  • Français

Patterns of gonadotropin secretion in cyclic Finn ewes selected for and against high ovulation rate

Published online by Cambridge University Press:  02 September 2010

W. Haresign ,
A. C. Cooper ,
M. Khalid  and
J. P. Hanrahan
W. Haresign
Affiliation:
University of Nottingham Faculty of Agricultural and Food Sciences, Sutton Bonington, Loughborough LE12 5RD
A. C. Cooper
Affiliation:
Teagasc, Belclare, Tuam, Co. Galway, Ireland
M. Khalid
Affiliation:
University of Nottingham Faculty of Agricultural and Food Sciences, Sutton Bonington, Loughborough LE12 5RD
J. P. Hanrahan
Affiliation:
Teagasc, Belclare, Tuam, Co. Galway, Ireland
Get access

Abstract

A comparison of the patterns of LH and FSH secretion was undertaken in lines of Finn sheep selected for and against high ovulation rate. Mean ovulation rate was significantly higher in the high line ewes (mean 4·1) compared with both the control (mean 2·5) and low line (mean 2·7) ewes (P <0·01). The pre-ovulatory LH peak occurred significantly earlier in the high line ewes (mean 52·1 h) compared with both the control (mean 65·0 h) and low line (mean 59·0 h) ewes (P < 0·05). While mean LH pulse frequency and overall mean LH concentrations were both significantly higher during the follicular compared with the luteal phase of the cycle (P < 0·05), there were no consistent relationships between patterns of pulsatile LH secretion and ovulation rate among the three selection lines. Plasma FSH concentrations remained significantly higher over the entire follicular phase of the oestrous cycle in the high line ewes compared with both the control and low line ewes (P < 0·05). It is suggested that the ovulation rate achieved by high line ewes may be causally related to their higher follicular phase FSH concentrations.

Keywords

ewesgonadotropin releaseovulation rate
Type
Research Article
Information
Animal Science , Volume 61 , Issue 2 , October 1995 , pp. 251 - 257
Copyright
Copyright © British Society of Animal Science 1995

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

Adashi, E. Y. 1989. Putative intraovarian regulators. In Seminars in reproductive endocrinology, vol. 7 (ed. Adashi, E. Y.). Thieme Medical Publishers, New York.Google Scholar
Adams, T. E., Quirke, J. F., Hanrahan, J. P., Adams, B. M. and Watson, J. G. 1988. Gonadotrophin secretion during the periovulatory period in Galway and Finnish Landrace ewes and Finnish Landrace ewes selected for high ovulation rate, journal of Reproduction and Fertility 83: 575–584.Google Scholar
Bindon, B. M., Blanc, M. R., Pelletier, J., Terqui, M. and Thimonier, J. 1979. Periovulatory gonadotropin and ovarian steroid patterns in sheep of breeds with different fecundity. Journal of Reproduction and Fertility 55: 15–25.CrossRefGoogle Scholar
Bindon, B. M., Piper, L. R., Cummins, L. J., O'Shea, T., Hillard, M. A., Findlay, J. K. and Robertson, D. M. 1985. Reproductive endocrinology of prolific sheep: studies of Booroola Merino. In Genetics of reproduction in sheep (ed. Land, R. B. and Robinson, D. W.), pp. 217–235. Butterworths, London.Google Scholar
Cahill, L. P., Saumande, K., Ravault, J. P., Blanc, M., Thimonier, J., Mariana, J. C. and Mauleon, P. 1981. Hormonal and follicular relationships in ewes of high and low ovulation rates. Journal of Reproduction and Fertility 62: 141–150.CrossRefGoogle ScholarPubMed
Dodson, S. E., Abbott, M. P. and Haresign, W. 1988. Comparison of bioassay and radioimmunoassay data for study of changes in the pattern of LH secretion from birth to puberty in the heifer. Journal of Reproduction and Fertility 82: 539–543.CrossRefGoogle ScholarPubMed
Driancourt, M. A., Gauld, I. K., Terqui, M. and Webb, R. 1986. Variations in patterns of follicle development in prolific breeds of sheep, journal of Reproduction and Fertility 78: 565–575.CrossRefGoogle ScholarPubMed
Hanrahan, J. P. 1982. Selection for increased ovulation rate, litter size and embryo survival. Proceedings of the second world congress on genetics applied to livestock production, Madrid, vol. V, pp. 294–309.Google Scholar
Haresign, W. 1985. The physiological basis for variation in ovulation rate and litter size in sheep: a review. Livestock Production Science, 13: 3–20.Google Scholar
Lahlou-Kassi, A., Schams, D. and Glatzel, P. 1984. Plasma gonadotrophin concentrations during the oestrous cycle and after ovariectomy in two breeds of sheep with low and high fecundity. Journal of Reproduction and Fertility 70: 165–173.CrossRefGoogle ScholarPubMed
McLeod, B. J., Haresign, W. and Lamming, G. E. 1982a. The induction of ovulation and luteal function in seasonally anoestrous ewes treated with small-dose multiple injections of GnRH. Journal of Reproduction and Fertility 65: 215–221.CrossRefGoogle ScholarPubMed
McLeod, B. J., Haresign, W. and Lamming, G. E. 1982b. Response of seasonally anoestrous ewes to small-dose multiple injections of GnRH with and without progesterone pretreatment. journal of Reproduction and Fertility 65: 223–230.CrossRefGoogle ScholarPubMed
McNatty, K. P., Fisher, M., Collins, F., Hudson, N. L., Heath, D. A., Ball, K and Henderson, K. M. 1989. Differences in the plasma concentrations of FSH and LH in ovariectomized Booroola FF and ++ ewes. Journal of Reproduction and Fertility 85: 705–713.Google Scholar
McNatty, K. P., Hudson, N., Gibb, M., Ball, K., Henderson, K. M., Heath, D. A., Lun, D. A. and Kieboom, L. E. 1985. FSH influences follicle viability, oestradiol biosynthesis and ovulation rate in Romney ewes. Journal of Reproduction and Fertility 75: 121–131.CrossRefGoogle ScholarPubMed
McNatty, K. P., Hudson, N., Henderson, K. M., Gibb, M., Morrison, L., Ball, K. and Smith, P. 1987. Differences in gonadotrophin concentrations and pituitary responsiveness to GnRH between Booroola ewes which were homozygous (FF), heterozygous (F+) and non-carriers (++) of a major gene influencing their ovulation rate, journal of Reproduction and Fertility 80: 577–588.Google Scholar
McNeilly, A. S., Picton, H. M., Campbell, B. K. and Baird, D. T. 1991. Gonadotropic control of follicle growth in the ewe. journal of Reproduction and Fertility, suppl. 43: pp. 177–186.Google Scholar
Reiter, E. O., Beitins, I.Z., Ostrea, T. and Gutai, J. P. 1982. Bioassayable luteinizing hormone during childhood and adolescence and patients with delayed pubertal development. Journal of Clinical Endocrinology and Metabolism 54: 155–161.CrossRefGoogle ScholarPubMed
Rhind, S. M., Leslie, I. D., Gunn, R. G. and Doney, J. M. 1985. Plasm FSH, LH, prolactin and progesterone profiles of Cheviot ewes with different levels of intake before and after mating, and associated effects on reproductive performance. Animal Reproduction Science 8: 301–313.Google Scholar
Scaramuzzi, R. J. and Radford, H. M. 1983. Factors regulating ovulation rate in the ewe. Journal of Reproduction and Fertility 69: 353–367.Google Scholar
Webb, R. and England, B. G. 1982. Identification of the ovulatory follicle in the ewe: associated changes in follicular size, thecal and granulosa cell luteinizing hormone receptors, antral fluid steroids, and circulating hormones during the preovulatory period. Endocrinology 110: 873–881.CrossRefGoogle ScholarPubMed
Zalesky, D. D., Nett, T. M. and Grotjan, H. E. 1992. Ovine luteinizing hormone — isoforms in the pituitary during the follicular and luteal phases of the estrous cycle and during anestrus. Journal of Animal Science 70: 3851–3856.Google Scholar