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On fitting curves to lactation data

Published online by Cambridge University Press:  02 September 2010

J. M. Cobby  and
Y. L. P. Le Du
J. M. Cobby
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire SL6 5LR
Y. L. P. Le Du
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire SL6 5LR
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Abstract

The usual method of fitting the model y = Anb exp(−cn) to lactation data, by a multiple regression of logey on n and logen, can result in an ill-fitting curve. An analysis of the untransformed data provides a better fit but requires more extensive computation and a simple approximation to this procedure is given. Since the parameters of this model have no direct biological interpretation two alternative models are introduced, each having a parameter measuring the persistency of lactation.

Type
Research Article
Information
Animal Production , Volume 26 , Issue 2 , April 1978 , pp. 127 - 133
Copyright
Copyright © British Society of Animal Science 1978

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References

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