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Influence of farm, parity, season and litter size on the lactation curve parameters of white British dairy goats

Published online by Cambridge University Press:  02 September 2010

J. C. Williams
J. C. Williams
Affiliation:
Department of Agriculture, University of Reading, Reading RG6 2AT
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Abstract

The following goat lactation model was fitted (using non-linear regression) to 407 lactations from five commercial goat dairies and one Research Institute goat herd: y = A exp (B(l + n'/2)n' + Cn' 2 - 1·01/n) where y = daily yield in kg; n = day of lactation (post parturition); and n' = (n -150)1100.

Influence of farm, parity and season on the parameter estimates for 376 individual lactations was studied, using multiple linear regression. The models adopted were of the form: A = 1·366 + 1·122 × parity - 0·137 × parity2; ln(-B) = - 1·711 + 0·107 × parity + 0·512 season one; C = 0·037, with a standard deviation for A of 0·658, for ln(-B) of 0·636 and for C of 0·127.

Influence of litter size on parameters was investigated for the Research Institute herd. There was no evidence of an effect on any of the model parameters.

Keywords

dairy goatslactation curveUtter sizeparityseasonality
Type
Research Article
Information
Animal Production , Volume 57 , Issue 1 , August 1993 , pp. 99 - 104
Copyright
Copyright © British Society of Animal Science 1993

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