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The effect of long photoperiod or bromocryptine treatment on prolactin concentration and fertility in ewe lambs mated at induced oestrus

Published online by Cambridge University Press:  02 September 2010

N. F. G. Beck ,
M. C. G. Davies  and
B. Davies
N. F. G. Beck
Affiliation:
Department of Agricultural Sciences, University of Wales, Aberystwyth, Penglais, Aberystwyth, Dyfed SY23 3DD
M. C. G. Davies
Affiliation:
Department of Agricultural Sciences, University of Wales, Aberystwyth, Penglais, Aberystwyth, Dyfed SY23 3DD
B. Davies
Affiliation:
Department of Agricultural Sciences, University of Wales, Aberystwyth, Penglais, Aberystwyth, Dyfed SY23 3DD
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Abstract

An investigation was conducted into the effects of increasing plasma prolactin concentration with long photoperiod or suppressing it with bromocryptine on the fertility of ewe lambs. One hundred and twenty dim Forest ewe lambs were divided into three groups: group C was kept as a control; group L was exposed to a long photoperiod (16 h light: 8 h dark) and group B was given daily injections of 1 mg bromocryptine from 12 days before until 21 days after mating. All three groups were mated in late November, 30 days after housing, following progestagen/PMSG treatment. Post-mating prolactin concentrations were significantly higher in group L and lower in group B compared with group C (P > 0·05). There was a tendency for pregnancy rate and the number of corpora lutea to be represented by viable foetuses to be lower in group L than in group C (P < 0·05). Furthermore, post-mating progesterone concentration was higher in this group compared with those in group C (P > 0·05). In a second experiment, 100 Welsh Χ Texel ewe lambs were given treatment C or L. Embryo survival tended to be lower and crown rump length, embryo weight and amniotic sac width were reduced at 25 days post mating in the animals given treatment L, compared with those given treatment C (P < 0·05). The combined results of the experiments indicated that fewer corpora lutea were represented by viable embryos or foetuses in group L than in group C (P < 0·05). These results suggest that embryo growth and survival is reduced in animals bred under a long photoperiod.

Keywords

bromocryptineembryosewe lambsfertilityphotoperiod
Type
Research Article
Information
Animal Science , Volume 60 , Issue 2 , April 1995 , pp. 209 - 214
Copyright
Copyright © British Society of Animal Science 1995

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References

Abraham, G. E., Swerdloff, R., Tulchinsky, D. and Odell, W. D. 1971. Radioimmunoassay of progesterone. Journal of Clinical Endocrinology and Metabolism 32: 619–624.CrossRefGoogle ScholarPubMed
Aitken, R. P., Wallace, J. M. and Robinson, J. J. 1990. A note on conception rates and litter sizes following the intrauterine insemination of ewes at an induced oestrus during seasonal anoestrus. Animal Production 50: 379–382.Google Scholar
Ashworth, C. J., Sales, D. I. and Wilmut, I. 1989. Evidence of an association between the survival of embryos and the periovulatory plasma progesterone concentration in the ewe. Journal of Reproduction and Fertility 87: 23–32.CrossRefGoogle ScholarPubMed
Beck, N. F. G. and Davies, M. C. G. 1989. Luteal function and plasma prolactin during the first and third oestrous cycles in ewe lambs. Journal of Reproduction and Fertility Abstract Series 3, p. 56 (abstr.).Google Scholar
Beck, N. F. G. and Davies, M. C. G. 1994. The effect of stage of breeding season or premating oestrogen and progestagen therapy on fertility in ewe lambs. Animal Production 59: 429–434.Google Scholar
Bevers, M. M. and Dieleman, S. J. 1987. Effect of chronic treatment with bromocryptine on the corpus luteum function of the cow. Animal Reproduction Science 14: 95–101.CrossRefGoogle Scholar
Bryden, M. M., Evans, H. E. and Binns, W. 1972. Embryology of the sheep. 1. Extraembryonic membranes and the development of body form. Journal of Morphology 138: 169–186.CrossRefGoogle Scholar
Davies, M. C. G. and Beck, N. F. G. 1992. Plasma hormone profiles and fertility in ewe lambs given progestagen supplementation after mating. Theriogenology 38: 513–526.CrossRefGoogle ScholarPubMed
Denamur, J. 1974. Luteotrophic factors in sheep. Journal of Reproduction and Fertility. 38: 251–259.CrossRefGoogle Scholar
Dyrmundsson, O. R. 1983. The influence of environmental factors on the attainment of puberty in ewe lambs. In Sheep production (ed. Haresign, W.), pp. 393–408. Butterworths, London.Google Scholar
Ebling, F. J. P. and Foster, D. L. 1988. Photoperiod requirements for puberty differ from those for the onset of the adult breeding season in female sheep. Journal of Reproduction and Fertility 84: 283–293.CrossRefGoogle ScholarPubMed
El Shiekh, A. S., Hulet, C. V., Pope, A. L. and Casida, L. E. 1955. The effect of level of feeding on the reproductive capacity of ewes. Journal of Animal Science 14: 919–929.CrossRefGoogle Scholar
Fitzgerald, J. A. and Butler, W. R. 1988. Sexual maturation of ewes raised without ram exposure in a controlled lighting environment. Theriogenology 29: 811–821.CrossRefGoogle Scholar
Forbes, J. M., Driver, P. M., Brown, W. B., Scanes, C. G. and Hart, I. C. 1979. The effect of daylight on the growth of lambs 2. Blood concentrations of growth hormone, prolactin, insulin and thyroxine, and the effect of feeding. Animal Production 29: 43–51.Google Scholar
Foote, W. C., Pope, A. L., Chapman, A. B. and Casida, L. E. 1959. Reproduction in yearling ewes as affected by breed and sequence of feeding levels. II. Effect on fetal development. Journal of Animal Science 18: 463–474.CrossRefGoogle Scholar
Hamra, A. M. and Bryant, M. J. 1979. Reproductive performance during mating and pregnancy in young female sheep. Animal Production 28: 235–243.Google Scholar
Haresign, W. 1990. Controlling reproduction in sheep. In New developments in sheep production (ed. Slade, C. F. R. and Lawrence, T. L. J.), British Society of Animal Production, occasional publication, no. 14, pp. 23–37.Google Scholar
Hendy, C. R. C. and Bowman, J. C. 1978. The association between variations in the seasonal onset of oestrus and litter size in the ewe. Journal of Reproduction and Fertility 40: 105–112.CrossRefGoogle Scholar
Hulet, C. V., Foote, W. C. and Price, D. A. 1969. Factors affecting growth of ovine foetuses during early gestation. Animal Production 11: 219–223.Google Scholar
Keisler, D. H., Inskeep, E. K. and Dailey, R. A. 1983. First luteal tissue in ewe lambs: influence on subsequent ovarian activity and response to hysterectomy. Journal of Animal Science 57: 150–156.CrossRefGoogle ScholarPubMed
Lees, J. L. 1978. Factors affecting puberty and mating behaviour in sheep. In The management and diseases of sheep (ed. Council, British), pp. 124–151. British Council and Commonwealth Agricultural Bureaux.Google Scholar
McNeilly, A. S. 1980. Prolactin and the control of gonadotrophin secretion in the female. Journal of Reproduction and Fertility 58: 537–549.CrossRefGoogle ScholarPubMed
McNeilly, A. S. and Andrews, P. 1974. The purification and characterisation of caprine prolactin. Journal of Endocrinology 60: 359–367.CrossRefGoogle ScholarPubMed
McNeilly, A. S., Glasier, A., Jonassen, J. and Howie, P. W. 1982. Evidence of direct inhibition of ovarian function by prolactin. Journal of Reproduction and Fertility 65: 559–569.CrossRefGoogle ScholarPubMed
McNeilly, A. S. and Land, R. B. 1979. Effect of suppression of plasma prolactin on ovulation, plasma gonadotrophins and corpus luteum function in LH-RH treated anoestrous ewes. Journal of Reproduction and Fertility 56: 601–609.CrossRefGoogle ScholarPubMed
Quirke, J. F., Adams, T. E. and Hanarahan, J. P. 1983. Artificial induction of puberty in ewe lambs. In Sheep production (ed. Haresign, W.), pp. 409–429. Butterworths, London.Google Scholar
Rhind, S. M., Chesworth, J. M. and Robinson, J. J. 1978. A seasonal difference in ovine peripheral plasma prolactin and progesterone concentrations in early pregnancy and in relationship between the two hormones. Journal of Reproduction and Fertility 52: 79–81.CrossRefGoogle ScholarPubMed
Rhind, S. M., Robinson, J. J., Chesworth, J. M. and Crofts, R. J. M. 1980. Effects of season, lactation and plane of nutrition on prolactin concentrations in ovine plasma and the rôle of prolactin in the control of ewe fertility. Journal of Reproduction and Fertility 58: 145–152.CrossRefGoogle ScholarPubMed
Smith, I. D. 1967. The effect of constant long daily photoperiod upon the onset of puberty in ewes. Journal of Agricultural Science, Cambridge 69: 43–45.CrossRefGoogle Scholar
Wathes, D. C. 1992. Embryonic mortality and the uterine environment. Journal of Endocrinology 134: 321–325.CrossRefGoogle ScholarPubMed
Wilmut, I., Sales, D. I. and Ashworth, C. J. 1986. Maternal and embryonic factors associated with prenatal loss in mammals. Journal of Reproduction and Fertility 76: 851–864.CrossRefGoogle ScholarPubMed