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Fertility in Scottish Blackface ewes as influenced by nutrition and body condition at mating

Published online by Cambridge University Press:  27 March 2009

R. G. Gunn
Affiliation:
Hill Farming Research Organisation, 29 Lauder Road, Edinburgh, 9
J. M. Doney
Affiliation:
Hill Farming Research Organisation, 29 Lauder Road, Edinburgh, 9
A. J. F. Russel
Affiliation:
Hill Farming Research Organisation, 29 Lauder Road, Edinburgh, 9

Summary

Two-hundred-and-seventy-three Scottish Blackface ewes in three ages (5, 4 and 2 years) were differentially group fed over 6 weeks in such a manner that at 6 weeks before mating there were approximately equal numbers in each of six subjectively assessed body condition groups ranging from score 1 (lean) to score 3½ (moderately fat). Over the 6 weeks prior to mating these groups were either well fed, fed at about maintenance, or underfed so that at mating the maj ority of ewes were in either condition 1½ or 3.

A predetermined random sample of mature ewes from each of the six original condition groups was killed 2–3 days post-mating for ovulation counts. Surviving ewes were fed above maintenance post-mating and the number of lambs recorded at birth. Condition at mating had a significant, positive effect on both ovulation and lambing rates but had no effect on infertility measured as the difference between them.

The level of food intake prior to and at mating had no effect on either ovulation or lambing rates of moderately fat ewes (condition 3) but the results can be interpreted as indicating that the level of food intake had a positive effect on both ovulation and lambing rates of lean ewes (condition 1½).

Type
Research Article
Copyright
Copyright © Cambridge University Press 1969

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References

Coop, I. E. (1962) Liveweight-produotivity relationships in sheep. I. Liveweight and reproduction. N.Z. Jl agric Res. 5, 249–64.CrossRefGoogle Scholar
Coop, I. E. (1966). Effect of flushing on reproductive performance of ewes. J. agric. Sci., Camb. 67, 305–23.CrossRefGoogle Scholar
Edey, T. N. (1967). Early embryonic death and subsequent cycle length in the ewe. J. Eeprod. Fert. 13, 437–43.CrossRefGoogle ScholarPubMed
Gunn, R. G. (1967). Hill Farming Research Organisation, Fourth Report 1964–67. Hill Farming Research Organisation, Edinburgh.Google Scholar
Jefferies, B. C. (1961). Body condition scoring and its use in management. Tasm. J. Agric. 32, 1921.Google Scholar
Killeen, I. D. (1967). The effects of body weight and level of nutrition before, during and after joining on ewe fertility. Aust. J. exp. Agric. Anim. Husb. 7, 126–36.CrossRefGoogle Scholar
Mcinnes, P. & Smith, M. D. (1966). The effect of nutrition before mating on the reproductive performance of Merino ewes. Aust. J. exp. Agric. Anim. Husb. 6, 455–9.CrossRefGoogle Scholar
Russel, A. F. J., Doney, J. M. & Gunn, R. G. (1969). Subjective assessment of body fat in live sheep. J. agric. Sci., Camb. 72, 451–4.CrossRefGoogle Scholar
Tribe, D. E. & Seebeck, R. M. (1962). Effect of live weight and live-weight change on the lambing performance of ewes. J. agric. Sci., Camb. 59, 105–10.CrossRefGoogle Scholar
Wallace, L. R. (1961). Influence of liveweight and condition on ewe fertility. Proc. Ruakura Fmrs' Conf. Week.Google Scholar