The milking speed is evaluated on a scale of 1 (very slow) to 5 (very fast), and milking temperament on a scale of 1 (slow and gentle animal) to 3 (excitable or aggressive animal). Trained zootechnicians assess the phenotypic evaluation of cows in terms of milking traits during the second test milking in the first lactation.
| Trait | h2 |
| Milking speed | 0.12 |
| Milking temperament | 0.09 |
Model #
Breeding values for workability traits were estimated using the BLUP method – a multi-trait animal model that takes into account the following factors in a linear model: linear and quadratic regression on cow age at calving, a constant effect of herd-year-season-classifier, a constant effect of lactation stage at which the phenotypic evaluation was made, as well as a random additive animal effect and the influence of random error.
Breeding values for both traits were expressed as deviations from the base average and then transformed into a variable with a mean of 100 and a standard deviation of 10.
For milking speed (MS), a higher breeding value of the bull indicates that his daughters on average have a faster milking. For milking temperament (MT), a higher breeding value of the bull indicates that his daughters are generally calmer.
Genetic database #
The genetic base was taken as the average breeding value of bulls born between 2009-2011, evaluated based on at least 20 daughters in at least 10 heards.