Application of reactions norms in study of genotype environmental interaction for milk yield of buffaloes
Carregando...
Data
Orientador
Coorientador
Pós-graduação
Curso de graduação
Título da Revista
ISSN da Revista
Título de Volume
Editor
Tipo
Trabalho apresentado em evento
Direito de acesso
Resumo
The aim of this study was to estimate genetic parameters for milk yield (MY) in buffaloes using reaction norms. Model included the additive direct effect as random and contemporary group (herd and year of birth) were included as fixed effects and cow age classes (linear) as covariables. The animal additive direct random effect was modeled through linear Legendre polynomials on environment gradient (EG) standardized means. Mean trends were taken into account by a linear regression on Legendre polynomials of environmental group means. Residual variance was modeled trough 6 heterogeneity classes (EG). These classes of residual variance was formed: EG1: mean = 866,93 kg (621,68 kg-1011,76 kg); EG2: mean= 1193,00 kg (1011,76 kg-1251,49 kg); EG3: mean= 1309,37 kg (1251,49 kg -1393,20 kg); EG4: mean= 1497,59 kg (1393,20 kg- 1593,53 kg); EG5: mean =1664,78 kg (1593,53 kg -1727,32kg) e EG6: mean= 1973,85 kg (1727,32 kg -2422,19 kg).(Co)variance functions were estimated by restricted maximum likelihood (REML) using the GIBBS3F90 package. The heritability estimates for MY raised as the environmental gradient increased, varying from 0.20 to 0.40. However, in intermediate to favorable environments, the heritability estimates obtained with Considerable genotype-environment interaction was found for MY using reaction norms. For genetic evaluation of MY is necessary to consider heterogeneity of variances to model the residual variance.
Descrição
Palavras-chave
Environment gradient, Legendre, Random regression
Idioma
Inglês
Citação
Buffalo Bulletin, v. 32, n. SPECIAL ISSUE 2, p. 662-665, 2013.
Itens relacionados
Financiadores
Outras formas de acesso
