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Technical Note: Adaptation of an Animal-Model Method for Approximation of Reliabilities to a Sire-Maternal Grandsire Model

Permanent URL:
http://handle.nal.usda.gov/10113/22205
File:
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Abstract:
A method used to approximate reliabilities for animal models was modified to estimate reliabilities for sire-maternal grandsire (MGS) models. Accuracy of the approximation was tested on a calving-ease data set for 2,968 bulls for which the inverse of the coefficient matrix could be obtained. Correlations between estimated and true reliabilities ranged from 0.984 to 0.998 for first- and later-parity calving ease for sire and MGS effects. With no modification of the animal-model procedure, MGS identification was treated as if it were dam identification, which resulted in overestimated reliability. When pedigree information was ignored, reliability was underestimated. Correlations with true values were lower for both of those cases when compared with correct processing of MGS information. The modification provided a slight improvement over assuming MGS to be unknown and will be used for routine USDA evaluation of calving traits.
Author(s):
Wiggans, G.R. , Tsuruta, S. , Misztal, I.
Subject(s):
animal models , reliability , sires , genetic relationships , bulls , accuracy , calving , ease of birth , genetic correlation , traits
Format:
p. 4058-4061.
Note:
Includes references
Source:
Journal of dairy science 2008 Oct., v. 91, no. 10
Language:
English
Publisher:
American Dairy Science Association
Year:
2008
Collection:
Journal Articles, USDA Authors, Peer-Reviewed
Rights:
Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.