Evaluation of Autoregressive Covariance Structures for Test-Day Records of Holstein Cows: Estimates of Parameters
نویسندگان
چکیده
منابع مشابه
Evaluation of autoregressive covariance structures for test-day records of Holstein cows: estimates of parameters.
The objective of this study was to compare test-day (TD) models with autoregressive covariance structures for the estimation of genetic and environmental components of variance for milk, fat and protein yields, and somatic cell score (SCS) in Holstein cows. Four models were compared: model I (CS model) was a simple TD repeatability animal model with compound symmetry covariance structure for en...
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estimation of genetic parameters for milk production trait in holstein cows of the mazandaran gavdasht herd using test day records
random regression models (rrm) are used for genetic estimations of milk traits in dairy cows. rrm utilize data on traits that are repeated during the time, such as milk trait, which allows of the evaluation of the test day production information. in this study, to estimate genetic parameters for milk production trait, test day records (tdr) were collected from the first lactation of holstein co...
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ژورنال
عنوان ژورنال: Journal of Dairy Science
سال: 2005
ISSN: 0022-0302
DOI: 10.3168/jds.s0022-0302(05)72940-4