Conversions Interbull

Conversion factors production and conformation
The breeding value of the country of origin can only be converted to the Dutch base for Black & White sires if the Interbull breeding value of a sire is not known or if a new foreign breeding value is published. In those cases the conversion is done using the conversion factors below, which have been set by Interbull.

Conversion factors production and conformation for Holstein on Black & White basis

The converted breeding values for % fat, % protein and Inet are calculated using the breeding values for kg milk, kg fat and kg protein. See Calculating breeding values for % fat and % protein per basis

Conversion foreign breeding values
Foreign breed values of sires are converted by Interbull. Interbull makes the converted breeding value available to the computer centre that publishes the sire indexes in the Netherlands and Flanders.

Currently, Interbull converts breeding values for milk production traits, conformation, life span, birth traits (birth process and vitality), somatic cell count and fertility. These conversions are done for several main groups/breeds: Holstein (Black & White and Red & White), Jersey, Brown Swiss, Simmental (including Fleckvieh and Montbeliarde), Guernsey and Red Dairy Cattle (including Ayrshire and Scandinavian Red breeds). The sire indexes for the Netherlands and Flanders are used in the conversions of Holstein, Jersey, Brown Swiss, Simmental and Red Dairy Cattle. There is not enough data from the Netherlands and Flanders available for the conversion for Guernsey.

The tables displayed below show an overview for Holstein, Jersey, Brown Swiss, Simmental and Red Dairy Cattle of the countries and trait groups for which an Interbull conversion exists.

Holstein (Black & White and Red & White)


Brown Swiss

Simmental (Fleckvieh and Montbéliarde) 

RDC (Red Dairy Cattle)