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On estimating lactation yield

Published online by Cambridge University Press:  27 March 2009

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

Extract

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

Type
Short Notes
Copyright
Copyright © Cambridge University Press 1984

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