Transmission of +750 for kilos of milk, –0.10% for fat and +45 for kilos of protein. CRV publishes new breeding values for bulls three times a year. These breeding values are based on hard figures. Delta Potter P, for instance, owes his high breeding value for protein to the performance of his offspring. And L W Crescendo’s daughters ensure their sire is known for the generous quantities of milk he passes on.
These raw, uncorrected production figures form the basis of the estimated breeding values. The rule for all bulls is that daughter productions are only published if at least 75 milk records are available per lactation. Generally speaking, the more daughters a bull has, the closer the actual production figures correspond to the breeding values. Take Bouw Rocky and Apina Malcolm, for example. The duo shows a clearly different inheritance pattern for kilograms of milk. On paper Malcolm passes on around 1100 kilos more than Rocky. Half of that, about 550kg, should be apparent in the milk production of his daughters. The practice confirms this quite well: as heifers, Rocky daughters produce 8011kg and Malcolm’s daughters nearly 8500kg.
|305 day prod.|
|Apina Malcolm rf||2012||+1291||8499|
Table 1: Comparison of breeding value for milk production and actual daughter productions for a number of bulls