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A note on ovulation rate and embryonic survival in D'man ewes

Published online by Cambridge University Press:  02 September 2010

A. Lahlou-Kassi
Affiliation:
Department of Reproduction and Artificial Insemination, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco
M. Marie
Affiliation:
Department of Reproduction and Artificial Insemination, Hassan II Agronomic and Veterinary Institute, Rabat, Morocco
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Abstract

The elements of prolificacy have been analysed for the D'man sheep, a prolific Moroccan breed, by laparotomy on 38 animals. The average ovulation rate was 2·50 (s.e.0·45); a slight difference was observed between nulliparous and multiparous ewes due to high simultaneous activity by both ovaries in the latter group. Embryonic survival (42% overall) was 94% (87 to 100%) for multiparous and 44% (36 to 52%) for the nulliparous ewes at one ovulation, decreasing with increasing numbers of corpora lutea. The average litter size showed an optimum at four ovulations.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1981

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References

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