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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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