Application of random regression models using different data structures

Ciência Rural

Cardoso, Vera Lucia¹  Faro, Lenira El¹  Machado, Paulo Fernando²  Albuquerque, Lucia Galvão de³  Sousa Júnior, Severino Cavalcante de³  Bignardi, Annaiza Braga³ 

[1]Agência Paulista de Tecnologia dos Agronegócios, Ribeirão Preto, Brazil

[2]), Universidade de São Paulo, Piracicaba, Brazil

[3]Universidade Estadual Júlio de Mesquita, Jaboticabal, Brazil

关键词: dairy cattle;    genetic evaluation;    longitudinal dataINTRODUÇÃO:Os modelos de regressão aleatória (MRA) têm se tornado uma alternativa padrão para análises genéticas de dados longitudinais;   

DOI  :  10.1590/0103-8478cr20131082

学科分类：农业科学（综合）

来源: Universidade Federal de Santa Maria * Centro de Ciencias Rurais

【 摘 要 】

A total of 3.035 lactations of Holstein cows from four farms in the Southeast, to check the influence of data structure of milk yield on the genetic parameters. Four dataset with different structures were tested, weekly controls (CW) with 122.842 controls, monthly controls (CM) 30.883, bimonthly controls (CB) with 15,837 and quarterly controls (CQ) with 12,702. The random regression model was used and was considered as random additive genetic and permanent environment effects, fixed effects of the contemporary groups (herd-year-month of test-day) and age of cow (linear and quadratic effects). Heritability estimates showed similar trends among the data files analyzed, with the greatest similarity between dataset CS, CM and CB. The dataset submitted all the CB estimates of genetic parameters analyzed with the same trend and similar magnitude to the CS and CM dataset, allowing the claim that there was no influence of the data structure on estimates of covariance components for the dataset CS, CM and CB. Thus, milk recording could be accomplished in a CB structure

【 授权许可】

Unknown