Estimation of milkability breeding values and variance components for Italian Holstein

Summary: The importance of milking speed is growing due to the need for efficiency at the farm level; therefore, it is important to update and improve the statistical model for the estimation of breeding values for this trait. A strict data editing procedure was applied. The defined model was a single-trait repeatability threshold animal model. The results for heritability and repeatability were 0.275 and 0.5. The result of the genomic validation for reliability was 0.386, which is an improvement compared with the previous model. The genetic correlations of this trait confirmed that both extremes of the estimated breeding value must be treated cautiously.