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Embryo mortality in Scottish Blackface ewes as influenced by body condition at mating and by post-mating nutrition

Published online by Cambridge University Press:  27 March 2009

R. G. Gunn
Affiliation:
Hill Farming Research Organisation, 29 Lander Road, Edinburgh EH9 2JQ
J. M. Doney
Affiliation:
Hill Farming Research Organisation, 29 Lander Road, Edinburgh EH9 2JQ
A. J. F. Russel
Affiliation:
Hill Farming Research Organisation, 29 Lander Road, Edinburgh EH9 2JQ

Summary

One hundred and forty-nine Scottish Blackface ewes (aged 5 and 6 years), from two different farm sources, were group-fed over 6 weeks in such a manner that at 3 weeks before mating there were approximately equal numbers from each source in two widely different levels of subjectively assessed body condition (scores 1·5 and 3 on a scale ranging from 0 = emaciated to 5 = very fat). The majority of ewes were maintained in these levels of condition until mating after which they were allocated alternately to high and low planes of post-mating nutrition for 26±2 days.

Half the ewes in each group were killed on day 26±2, or earlier return-to-service, for ovulation and viable embryo counts. Surviving ewes were fed at or above maintenance until parturition and the number of lambs recorded.

Condition at mating had a significant, positive effect on both ovulation and lambing rates and had an apparent negative effect on embryo mortality up to day 26±2, although this was influenced by differences in the distributions of single and multiple shed ova. Post-mating nutrition had no effect on embryo mortality up to day 26±2. Neither condition at mating nor post-mating nutrition had any effect on embryo mortality from day 26±2 to parturition.

Source of ewe had a significant effect on both ovulation rate and embryo mortality at both levels of body, condition.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1972

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References

Braden, A. W. H. (1971). Studies in flock mating of sheep. 3. Effect of undernutrition of ewes during joining. Aust. J. exp. Agric. Anim. Rush. 11, 375–8.CrossRefGoogle Scholar
Casida, L. E., Woody, C. O. & Pope, A. L. (1966). Inequality in function of the right and left ovaries and uterine horns of the ewe. J. Anim. Sci. 25, 1169–71.CrossRefGoogle ScholarPubMed
Coop, I. E. & Clark, V. R. (1969). The influence of nutritional level in early pregnancy of the ewe. J. agric. Sci., Camb. 73, 387–94.CrossRefGoogle Scholar
Edey, T. N. (1967). Early embryonic death and subsequent cycle length in the ewe. J. Reprod. Fert. 13, 437–43.CrossRefGoogle ScholarPubMed
Edey, T. N. (1969). Prenatal mortality in the sheep: A review. Anim. Breed. Abstr. 37, 173–90.Google Scholar
Edey, T. N. (1970a). Nutritional stress and preimplantation embryonic mortality in Merino sheep, 1965. J. agric. Sci., Camb. 74, 181–6.CrossRefGoogle Scholar
Edey, T. N. (1970b). Nutritional stress and preimplantation mortality in Merino sheep (1964–7). General discussion and conclusions. J. agric. Sci., Camb. 74, 199204.CrossRefGoogle Scholar
Gunn, R. G., Doney, J. M. & Russel, A. J. F. (1969). Fertility in Scottish Blackface ewes as influenced by nutrition and body condition at mating. J. agric. Sci., Camb. 73, 289–94.CrossRefGoogle Scholar
Jeffeeies, B. C. (1961). Body condition scoring and its use in management. Tasm. J. Agric. 32, 19—21.Google Scholar
Kllleen, I. D. (1967). The effects of bodyweight and level of nutrition before, during and after joining on ewe fertility. Aust. J. exp. Agric. Anim. Husb. 7, 126–36.CrossRefGoogle Scholar
Rak, L. P. (1963). Embryonic mortality in Merinotype sheep. Anim. Breed. Abstr. 31, No. 370.Google Scholar
Russel, A. J. F., Doney, J. M. & Gunn, R. G. (1969). Subjective assessment of body fat in live sheep. J. agric. Sci., Camb. 72, 451–4.CrossRefGoogle Scholar
Russel, A. J. F., Doney, J. M. & Gunn, R. G. (1971). The distribution of chemical fat in the bodies of Scottish Blackface ewes. Anim. Prod. 13, 503—9.Google Scholar