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Variation in the time of parturition of Merino and Dorset Horn ewes

Published online by Cambridge University Press:  27 March 2009

J. M. George
J. M. George
Affiliation:
C.S.I.R.O., Division of Animal Physiology, Pastoral Research Laboratory, Armidale, N.S.W., 2350, Australia
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Summary

In a comparison involving 1467 births significantly more Dorset Horn than Merino ewes lambed during the period 08.00–18.00 h. The distribution of lambing during the day differed significantly between breeds. The daytime patterns averaged over breeds, and differences between breeds in patterns, did not change from year to year. At winter and spring lambings, 37% of Merino and 62% of Dorset Horn ewes lambed during the day (08.00–18.00 h) while during summer the corresponding percentages were 23 and 39.

For both breeds, the percentages of primiparous and multiparous ewes lambing during the day period were approximately the same. For Dorset Horns, the proportions of single and multiple births occurring during the day were similar.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 73 , Issue 2 , October 1969 , pp. 295 - 299
Copyright
Copyright © Cambridge University Press 1969

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References

Arthur, G. H. (1961). Some observations on the behaviour of parturient farm animals with particular reference to cattle. Vet. Rev. 12, 75–84.Google Scholar
Charles, E. (1953). The hour of birth. Br. J. prev. soc. Med. 7, 43.Google ScholarPubMed
Crowther, A. N. (1966). Circadian rhythms in childbirth. St Bart's Hosp. J. 70, 386–9.Google Scholar
Ewbank, R. (1963). Predicting the time of parturition in the normal cow. Vet. Rec. 75, 367–71.Google Scholar
Liggins, G. C. (1968). Premature parturition after infusion of corticotrophin or cortisol into foetal lambs. J. Endocr. 42, 323–9.CrossRefGoogle ScholarPubMed
Liggins, G. C., Holm, L. W. & Kennedy, P. C. (1966). Prolonged pregnancy following surgical lesions of the foetal lamb pituitary. J. Reprod. Fert. 12, 419.Google Scholar
Lindahl, I. L. (1964). Time of parturition in ewes. Anim. Behav. 12, 231–4.CrossRefGoogle Scholar
Malek, J. (1952). The manifestation of biological rhythms in delivery. Gynaecologia 133, 365–72.Google ScholarPubMed
McCulloch, J. S. G. (1965). Tables for the rapid computation of the Penman Estimate of evaporation. E. Afr. agric. For. J. 30, 286–95.CrossRefGoogle Scholar
Simpson, A. S. (1952). Are more babies born at night? Brit. med. J. no. 4788.Google Scholar
Sutton, D. H. (1945). Gestation period. Med. J. Aust. p. 611.Google Scholar
Wallace, L. R. (1949). Observations of lambing behaviour in ewes. Proc. N.Z. Soc. Anim. Prod. 9, 85–96.Google Scholar