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Oestrus synchronization in ewes: the effect of combining a prostaglandin analogue with a GnRH agonist (buserelin)

Published online by Cambridge University Press:  02 September 2010

N. F. G. Beck
Affiliation:
Welsh Institute of Rural Studies, University of Wales Aberystwyth, Penglais, Aberystwyth, Dyfed SY23 3DD
M. Jones
Affiliation:
Welsh Institute of Rural Studies, University of Wales Aberystwyth, Penglais, Aberystwyth, Dyfed SY23 3DD
B. Davies
Affiliation:
Department of Animal Health, Royal Veterinary College, Potters Bar EN6 1NB
A. R. Peters
Affiliation:
Department of Animal Health, Royal Veterinary College, Potters Bar EN6 1NB
S. P. Williams
Affiliation:
Welsh Institute of Rural Studies, University of Wales Aberystwyth, Penglais, Aberystwyth, Dyfed SY23 3DD
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Abstract

An experiment was designed to determine whether an injection of 4 μg of the GnRH agonist buserelin (GnRH) followed, 5 days later, by an injection of 100 μg of prostaglandin F2α analogue (PGF), would give a level of oestrus synchronization and fertility comparable with a standard double dose PGF regime. A total of 200 Welsh Halfbred ewes were divided by live weight into two treatment groups using a system of random stratification during the 1994 breeding season. Ninety-one percent of the ewes treated with GnRH combined with PGF were mated by fertile rams within a 3-day period compared with 94% of ewes treated with two injections of PGF, 11-days apart. Returns to service for the two groups were 11·1% and 7·4%, respectively. There was no effect of treatment on lambing performance, as a similar percentage of ewes in the GnRH plus PGF group (88·8%) and the double dose PGF group (92·5%) lambed to synchronized oestrus. Gestation length, litter size and lamb birth weight were similar for both groups. These results demonstrate that GnRH combined with PGF will produce levels of oestrus synchronization and fertility comparable with a double dose PGF regime.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1996

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References

Beck, N. F. G., Davies, M. C. G., Davies, B. and Lees, J. L. 1987. Oestrus synchronization and fertility in ewes: a comparison of three methods. Animal Production 44: 251254.Google Scholar
Beck, N. F. G., Davies, B. and Williams, S. P. 1993. Oestrous synchronization in ewes: the effect of combining a prostaglandin analogue with a 5-day protestagen treatment. Animal Production 56: 207210.Google Scholar
Beck, N. F. G., Peters, A. R. and Williams, S. P. 1994. The effect of GnRH agonist (buserelin) treatment on day 12 post mating on the reproductive performance of ewes. Animal Production 58: 243247.CrossRefGoogle Scholar
Fitzgerald, J. A., Ruggles, A. J., Stellflug, J. N. and Hansel, W. 1985. A seven-day synchronization method for ewes using medroxyprogesterone acetate (MAP) and prostaglandin F2α. Journal of Animal Science 61: 465469.CrossRefGoogle Scholar
Gordon, I. 1983. In Controlled breeding in farm animals (ed. Gordon, I.), pp. 181195. Permagon Press, London.CrossRefGoogle Scholar
Greyling, J. P. C., Westhuysen, J. M. van der and Neikerk, C. H. van. 1979. The synchronization of oestrus in sheep. 1. Dosage and time of prostaglandin administration following progestagen pretreatment. South African Journal of Animal Science 9:185192.Google Scholar
Henderson, D. C., Downing, J. M., Beck, N. G. F. and Lees, J. L. 1984. Oestrous synchronization in ewes: a comparison of prostaglandin F tham salt with a progestagen pessary. Animal Production 39: 229233.Google Scholar
Lightfoot, R. J. and Salmon, S. 1970. Fertility of ram spermatozoa frozen by the pellet method. 1. Transport and viability of spermatozoa within the genital tract of the ewe. Journal of Reproduction and Fertility 22: 385398.CrossRefGoogle Scholar
Twagiramungu, H., Guilbault, L. A., Proulx, J., Villeneuve, P. and Dufour, J. J. 1992. Influence of an agonist of GnRH (buserelin) on estrus synchronization and fertility in beef cows. Journal of Animal Science 70:19041910.CrossRefGoogle ScholarPubMed
Webb, R., Gong, J. G., Law, A. S. and Rusbridge, S. M. 1992. Control of ovarian function in cattle. Journal of Reproduction and Fertility, 45: suppl., pp. 141156.Google ScholarPubMed
Wolfenson, D., Thatcher, W. W., Savis, J. D., Badinga, L. and Lucy, M. C. 1994. The effect of a GnRH anologue on the dynamics of follicular development and synchronization of estrus in lactating cyclic dairy cows. Theriogenology 42: 633644.CrossRefGoogle Scholar