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On estimating lactation yield

Published online by Cambridge University Press:  27 March 2009

J. France  and
M. S. Dhanoa
J. France
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire, SL6 5LH
M. S. Dhanoa
Affiliation:
The Grassland Research Institute, Hurley, Maidenhead, Berkshire, SL6 5LH
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is generally used to describe the lactation curve in cattle, where yn (kg) is the average daily milk yield in the nth week of lactation (n = 1, 2, 3, …, N), a is a scale parameter, and b and c are shape parameters. The model was first proposed by Wood (1967) and is widely used in practice to describe the lactation curve for fat, protein, lactose and wholemilk production; it has also been used as a basis of a mathematical model for poultry egg production (McNally, 1971). Having estimated a, b and c by regression analysis, the total lactation yield Y (kg) can then be calculated as

Information

Type
Short Notes
Information
The Journal of Agricultural Science , Volume 103 , Issue 1 , August 1984 , pp. 245 - 247
Copyright
Copyright © Cambridge University Press 1984

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