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Multivariate REML estimates of genetic parameters of monthly test day milk production traits in first parity Iranian Holstein cows with the use of a repeatability test day model

Published online by Cambridge University Press:  20 November 2017

H. Farhangfar ,
P. Rowlinson  and
M. B. Willis
H. Farhangfar
Affiliation:
Department of Animal Science, Birjand University, Birjand, Iran
P. Rowlinson
Affiliation:
Department of Agriculture, University of Newcastle upon Tyne, NE1 7RU, U.K
M. B. Willis
Affiliation:
Department of Agriculture, University of Newcastle upon Tyne, NE1 7RU, U.K
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Extract

In practical dairy cattle breeding programmes, usually a small number of animals (selected from a large population) have a major influence on the genetic gain of the concerned population over a period of time (Hofer, 1998). Candidate animals are usually selected based on their breeding values that are predicted by using animal models. In order to predict breeding values, genetic parameters (calculated from variance and covariance components) of the traits under consideration should be estimated to be used in genetic evaluation systems either based on lactation or test day models. The use of test day models has increasingly become of interest in genetic evaluation of dairy cattle due to the fact that they can take more accurate account of the effects of environmental factors influencing test day milk yield over the course of lactation. The main objective of this study was to use a repeatability test day animal model to estimate genetic parameters of monthly test day milk production traits in first parity Iranian Holsteins.

Type
Genetics
Information
Proceedings of the British Society of Animal Science , Volume 2003 , 2003 , pp. 139
Copyright
Copyright © The British Society of Animal Science 2003

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References

Hofer, A. (1998) Variance component estimation in animal breeding: a review. Journal of Animal Breeding and Genetics 115:247–265.Google Scholar
Rekaya, R., Carabano, M. J. and Toro, M. A. (1999) Use of test day yields for the genetic evaluation of production traits in Holstein-Friesian cattle. Livestock Production Science 57:203–217.Google Scholar
Strabel, T. and Szwaczkowski, T. (1997) Additive genetic and permanent environmental variance components for test day milk traits in black- white cattle. Livestock Production Science 48:91–98.CrossRefGoogle Scholar