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A mathematical model of fertilization failure and early embryonic mortality in sheep

Published online by Cambridge University Press:  27 March 2009

P. A. Geisler ,
J. E. Newton  and
A. E. Mohan
P. A. Geisler
Affiliation:
Grassland Research Institute, Hurley, Maidenhead, Berks.
J. E. Newton
Affiliation:
Grassland Research Institute, Hurley, Maidenhead, Berks.
A. E. Mohan
Affiliation:
Grassland Research Institute, Hurley, Maidenhead, Berks.
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Summary

The reproductive potential of a sheep system is much reduced by the failure of released ova to be fertilized and to survive to parturition. This paper looks at currently available information on fertilization failure and early embryonic deaths. Separate hypotheses are proposed for fertilization and for early embryonic mortality. For fertilization, the hypothesis is that a ewe that mates with a ram will end up with either all or none of her released ova fertilized. For embryonic mortality, the hypothesis is that the survival of a fertilized ovum depends only on how many ova were released with it and is independent of the survival or death of those released with it. A mathematical model is constructed on these hypotheses and its predictions are compared with published experimental results of other workers.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 89 , Issue 2 , October 1977 , pp. 309 - 317
Copyright
Copyright © Cambridge University Press 1977

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