The impact of data structure on genetic (co)variance components of early growth in sheep, estimated using an animal model with maternal effects

摘要: Several studies have noted high negative correlations between maternal genetic and direct additive effects their influence on heritability of early growth traits in sheep. Multi-generation data from the Suffolk Sire Reference Scheme (SSRS) were used to investigate effect structure estimates (co)-variances for lamb 8-wk weight. In all analyses additive, genetic, environmental, residual fitted along with covariance effects. The contributions particular relationships studied by analyzing subsets SSRS data. A further eight formed having 10% or 50% dams own records one two, three four, five six, more than six offspring per dam. Analysis only record two yielded a correlation (-0.99) However, seven other sets dam higher proportion produced values -0.35 -0.51. Data number granddams are important determinants estimated traits.