where A is the numerator relationship matrix based on
pedigree, and I and R are the identity and a residual
matrices, respectively.
Breeding values for MY, FAT and PRT contents of the
animals were estimated by the single repeatability animal
model through REML method using ASReml 3 (Gilmour
et al., 2009). The EBVs of the whole dataset were used to
test association between milk production traits and the hr
genotype. The effect of genotype on ewes EBV was tested
for the three traits by analyzing least square means within
the one-way ANOVA using R software (R Development
Core Team, 2011). Moreover, the Tukey–Kramer multiple
comparison test was used to analyze significance of
differences between groups.