Hostname: page-component-848d4c4894-5nwft Total loading time: 0 Render date: 2024-05-17T07:48:50.360Z Has data issue: false hasContentIssue false
  • English
  • Français

Effect of mating management and PMSG dose on lambing outcome in ewes bred in late anoestrus

Published online by Cambridge University Press:  27 March 2009

M. P. Boland ,
T. F. Crosby  and
I. Gordon
M. P. Boland
Affiliation:
Department of Agriculture, University College, Lyons Estate, Newcastle, Co. Dublin, Eire
T. F. Crosby
Affiliation:
Department of Agriculture, University College, Lyons Estate, Newcastle, Co. Dublin, Eire
I. Gordon
Affiliation:
Department of Agriculture, University College, Lyons Estate, Newcastle, Co. Dublin, Eire
Get access Rights & Permissions [Opens in a new window]

Summary

Oestrus and ovulation was controlled by progestagen-impregnated sponges in 279 adult dry ewes in late anoestrus: at pessary withdrawal, ewes received doses of 0, 250, 500 or 750 i.u. pregnant mare serum gonadotrophin (PMSG). Rams were introduced to half the number of ewes which did not receive PMSG at the time of sponge withdrawal and to the remainder 48 h later. A significantly lower (P < 0·05) oestrous response was observed in ewes which did not receive PMSG but were introduced to rams at 48 h, when compared with ewes introduced to rams at time of sponge withdrawal. With iams introduced at 48 h a greater precision of synchronization was achieved by the use of PMSG (P < 0·05). Differences in conception rates were not evident between the various treatment groups, but a significantly higher (P < 0·05) litter size followed the use of the 750 i.u. PMSG dose.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 97 , Issue 2 , October 1981 , pp. 445 - 447
Copyright
Copyright © Cambridge University Press 1981

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

Baird, D. T. (1978). Pulsatile secretion of LH and ovarian oestradiol during the follicular phase in the sheep. Biology of Reproduction18, 359–364.CrossRefGoogle ScholarPubMed
Boland, M. P. (1972). Studies on oestrus in sheep following intravaginal progestagen treatment. Proceedings of the 1th International Congress on Animal Reproduction and Artificial Insemination (Munich) 2, 932–934.Google Scholar
Boland, M. P., Crosby, T. F. & Gordon, I. (1981). Induction of pregnancy in lactating anoestrous ewes. Journal of Agricultural Science, Cambridge 97, 465–467.CrossRefGoogle Scholar
Boland, M. P. & Gordon, I. (1973). Oestrus and ovulatory response to progestagen-PMS treatments in anoestrous ewes. Journal of the Irish Department of Agriculture and Fisheries 20, 65–70.Google Scholar
Boland, M. P. & Gordon, I. (1979). Effect of timing of ram introduction on fertility in progestagen-PMSG treated anoestrous ewes. Journal of Agricultural Science, Cambridge 92, 247–249.CrossRefGoogle Scholar
Boland, M. P., Kelleher, D. L. & Gordon, 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, 1 275–281.CrossRefGoogle Scholar
Chesworth, J. M. & Tait, A. (1974). A note on the effect of presence of rams upon the amount of luteinizing hormone in the blood of ewes. Animal Production 19, 109–110.Google Scholar
Hemsworth, P. H., Beilharz, R. G. & Brown, W. J. (1978). The importance of the courting behaviour of the boar on the success of natural and artificial matings. Applied Animal Ethology 4, 341–347.CrossRefGoogle Scholar
Martin, G. B., Oldham, C. M. & Lindsay, D. R. (1980). Increased plasma LH levels in seasonally anovular Merino ewes following the introduction of rams. Animal Reproduction Science 3, 125–132.CrossRefGoogle Scholar
Oldham, C. M. & Martin, G. B. (1978). Stimulation of seasonally anovular Merino ewes by rams. II. Premature regression of ram-induced corpora lutea. Animal Reproduction Science 1, 291–295.CrossRefGoogle Scholar
Oldham, C. M., Martin, G. B. & Knight, T. W. (1978). Stimulation of seasonally anovular Merino ewes by rams. I. Time from introduction of the rams to the preovulatory LH surge and ovulation. Animal Reproduction Science 1, 283–290.CrossRefGoogle Scholar
Scaramuzzi, R. J. & Baird, D. T. (1976). Ovarian steroid secretion in sheep during anoestrus. Proceedings of International Sheep Breeding Congress (Muresk) (ed. Tomes, G. J., Robertson, D. E. and Lightfoot, R. J.), pp. 330–337.Google Scholar
Scaramuzzi, R. J. & Martensz, N. D. (1975). Effects of active immunization against androstenedione on luteinizing hormone levels in the ewe. In Immunization with Hormones in Reproductive Research (ed. Nieschlag, B.), p. 141. Amsterdam: North-Holland Publishing Company.Google Scholar
Schinckel, P. G. (1954). The effect of the presence of the ram on the ovarian activity of the ewe. Australian Veterinary Journal 30, 189–195.CrossRefGoogle 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, 511–512.CrossRefGoogle Scholar