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Reproduction in young female sheep induced to breed at various ages

Published online by Cambridge University Press:  02 September 2010

R. M. H. Al-Wahab  and
M. J. Bryant
R. M. H. Al-Wahab
Affiliation:
Department of Agriculture and Horticulture, University of Reading, Earley Gate, Reading RG6 2AT
M. J. Bryant
Affiliation:
Department of Agriculture and Horticulture, University of Reading, Earley Gate, Reading RG6 2AT
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Abstract

Two hundred and thirteen Suffolk × (Cadzow Improver × Scottish Blackface) young female sheep were mated either after the natural occurrence of puberty or at 140, 182 and 224 days of age in Year 1 and 140 and 182 days of age in Year 2 after treatment with progestagen (MAP) and 750 i.u. PMS; 90 to 100% of sheep ovulated after hormone treatment. Few sheep were found with embryos or live lambs in Year 1, possibly because of inadequacies in artificial insemination. In Year 2, after natural mating, the incidences of cleaved ova, live embryos 26 days after mating and live lambs born were 82, 33 and 23% respectively for sheep mated at 140 days; 100, 31 and 23% respectively for sheep mated at 182 days; and 100, 62 and 31% respectively for sheep mated after puberty. The occurrence of a second post-treatment ovulation in sheep without embryos at 26 days increased with age at treatment.

Type
Research Article
Information
Animal Production , Volume 26 , Issue 3 , June 1978 , pp. 309 - 316
Copyright
Copyright © British Society of Animal Science 1978

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References

REFERENCES

Al Wahab, R. M. H. and Bryant, M. J. 1977. Reproductive success in ewe lambs mated at an induced puberty. Anim. Prod. 24: 129 (Abstr.).Google Scholar
Ducker, M. J. 1971. Photoperiodism in the ewe. Ph.D. Thesis, University of Reading.Google Scholar
Ducker, M. J. and Boyd, J. S. 1974. An evaluation of the vaginal smear technique for detecting the occurrence of ovulation in the ewe. J. Reprod. Fert. 41: 249–251.CrossRefGoogle ScholarPubMed
Dziuk, P. J. 1971. Obtaining eggs and embryos from sheep and pigs. In Methods in Mammalian Embryology (ed. Daniel, J. C. Jr), pp. 76–85. W. H. Freeman and Co, San Francisco.Google Scholar
Keane, M. G. 1974. Effect of progestagen-PMS hormone treatment on reproduction in ewe lambs. Ir. J. agric. Res. 13: 39–48.Google Scholar
Keane, M. G. 1975a. Effect of 17B oestradiol pre-treatment and system of mating on the reproductive performance of progestagen-PMS-treated, non-cyclic ewe lambs. Ir. J. agric. Res. 14: 7–13.Google Scholar
Keane, M. G. 1975b. Induction of oestrus and pregnancy in autumn-born ewe lambs. Ir. J. agric. Res. 14: 81–84.Google Scholar
Land, R. B. and McGovern, P. T. 1968. Ovulation and fertilisation in the lamb. J. Reprod. Fert. 15: 325–327.CrossRefGoogle ScholarPubMed
Mansour, A. M. 1959. The hormonal control of ovulation in the immature lamb. J. agric. Set, Camb. 52: 87–94.CrossRefGoogle Scholar
Segal, D. H. and Baker, R. D. 1973. Maintenance of corpora lutea in prepuberal gilts. J. Anim. Sci. 37: 762–767.CrossRefGoogle ScholarPubMed
Seidel, G. E., Larson, L. L., Spilman, C. H., Hahn, J. and Foote, R. H. 1971. Culture and transfer of calf ova. J. Dairy Sci. 54: 923–926.CrossRefGoogle ScholarPubMed
Shaw, G. A., McDonald, B. E. and Baker, R. D. 1971. Fetal mortality in the prepuberal gilt. Can. J. Anim. Sci. 51: 233–236.CrossRefGoogle Scholar
Thwaites, C. J. 1967. Embryo mortality in the heat stressed ewe. 1. The influence of breed. J. Reprod. Fert. 14: 5–14.CrossRefGoogle ScholarPubMed
Trounson, A. O., Willadsen, S. M. and Moore, R. M. 1977. Reproductive function in prepubertal lambs: ovulation, embryo development and ovarian steroidogenesis. J. Reprod. Fert. 49: 69–75.CrossRefGoogle ScholarPubMed
Wright, R. W., Anderson, G. B., Cupps, P. T., Drost, M. and Bradford, G. E. 1976. In vitro culture of embryos from adult and prepuberal ewes. J. Anim. Sci. 42: 912–917.CrossRefGoogle ScholarPubMed