LBG - FS2024 – Exercise 9

Author

Peter von Rohr

Problem 1: BLUP Animal Model

Use the data set given below to predict breeding values for the response variable Weight using a BLUP animal model. The model contains Herd as fixed effect and BreastCircumference as regression covariate. The heritability (\(h^2\)) which is the ratio between genetic variance \(\sigma_u^2\) and the phenotypic variance \(\sigma_y^2\) is set to \(h^2 = 0.25\).

Task

  • Set up mixed model equations
  • Use package ‘pedigreemm’ to get inverse of matrix \(A\)
  • Solve mixed model equations
  • Get estimates for fixed effects
  • Get solutions for random breeding values
  • Rank animals according to predicted breeding values

Solution

  • Set up mixed model equations. For this, we require indcidence matrices

The inverse numerator relationship matrix is obtained via pedigreemm

  • Solve mixed model equations
  • Get estimates for fixed effects
  • Get solutions for random breeding values
  • Rank animals according to predicted breeding values