Genomic breeding values (gEBV) for all traits will be based on mixed cow-bull reference population (120,000 reference cows, >38,000 bulls) instead of a bull reference population. Majority of the reference cows are from the whole-herd-genotyping project KuhVision i.e. unselected cows representing entire population. gEBV will be more precise and fit better for the German Holstein population. Therefore gEBV of individual animals will change more compared to former routine runs.
Following the current seen and future expected changes in milk market relative weighting of fat and protein amount in milk production index RZM will change to 1:2, i.e. more weight on fat.
More information is available here (translated article ‘Why switch to a mixed reference population?’ and 'New RZM formula' published in Milchrind 1/2019).