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Effect of dose of Gronolone in intravaginal sponges on lambing outcome to fixed-time artificial insemination

Published online by Cambridge University Press:  27 March 2009

P. A. Smith
Affiliation:
Department of Agriculture, University College Dublin, Lyons Estate, Newcastle, Co. Dublin
M. P. Boland
Affiliation:
Department of Agriculture, University College Dublin, Lyons Estate, Newcastle, Co. Dublin
I. Gordon
Affiliation:
Department of Agriculture, University College Dublin, Lyons Estate, Newcastle, Co. Dublin

Extract

Research has shown that it is now possible to control the oestrous cycle of ewes with a high degree of precision (Robinson et al. 1967; Gordon, 1975; Boland, Kelleher & Gordon, 1978). There is general agreement that a high concentration of progestagen, followed by rapid withdrawal and adequate ovarian stimulation is necessary for acceptable fertility (Robinson et al. 1967; Gordon, 1975; Colas, 1975). Application of artificial insemination in France has involved the use of a 40–45 mg Cronolone sponge (Cognie, Mariana & Thimonier, 1970; Colas et al. 1973) while controlled breeding in sheep in Ireland has been used in conjunction with a 30 mg Cronolone pessary (Gordon, 1975; Smith, Boland & Gordon, 1978, 1981). The present experiment was designed to compare the relative effectiveness of two doses of Cronolone (30 or 45 mg) when administered in conjunction with two quantities(375 or 750 i.u.) of pregnant mare serum gonadotrophin (PMSG), given by intramuscular injection.

Type
Short Note
Copyright
Copyright © Cambridge University Press 1981

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References

REFERENCES

Boland, M.P., Kelleher, D. L. & Gordok, I. (1978). Comparison of control of oestrus and ovulation in sheep by an ear implant (SC-21009) or by intravaginal sponge (Cronolone or MAP). Animal Reproduction Science 1, 275281.Google Scholar
Coonie, Y., Mariana, J.C. & Thimonier, J. (1970). Ovulation time in normal ewes and ewes treated with progestagen with or without an injection of PMSG. Annales de Biologie Animale, Biochimie, Biophysique 10, 1524.Google Scholar
Colas, G. (1975). The use of progestagen SC-9880 as an aid for artificial insemination in ewes. Annales de Biologie Animale, Biochimie, Biophysique 15, 317327.Google Scholar
Cola, G., Thimonier, J., Courot, M. & Ortovant, R. (1973). Fertility, prolificacy and fecundity during the breeding season of ewes artificially inseminated after treatment with flurogestone acetate. Annales de Zootechnique 22, 441451.Google Scholar
Gordon, I. (1975). The use of progestagens in sheep bred by natural and artificial insemination. Annales de Biologie Animale, Biochimie, Biophysique 15, 303315.CrossRefGoogle Scholar
Robinson, T. J., Moore, N. W., Holst, P. J. & Smith, J. F. (1967). The evaluation of several progestagens administered in intravaginal sponges for the synchronization of oestrus in the entire cyclic Merino ewe. Paper IV of The Control of the Ovarian Cycle in the Sheep (ed. Robinson, T. J.), pp. 76101. Sydney, N.S.W.: Sydney University Press.Google Scholar
Smith, P. A. (1977). Studies in the artificial insemination of sheep. Ph.D. thesis, National University of Ireland, Dublin.Google Scholar
Smith, P. A., Boland, M. P. & Gordon, I. (1978). Conception rate in ewes: effect of method of breeding and number of inseminations. Journal of Agricultural Science, Cambridge 91, 511512.Google Scholar
Smith, P. A., Boland, M. P. & Gordon, I. (1981). Effect of type of intravaginal progestagen on the outcome of fixed-time artificial insemination. Journal of Agricultural Science, Cambridge 96, 243245.Google Scholar