The aim of the study was to determine the length of life, productive life and lifetime productivity of Black-and-White cows (with a high share of Holstein-Friesian genes in their genotype) kept in the free barn system. Using source data contained in breeding records the following were calculated:

• intensity of culling of cows in terms of the cause and year of culling,
• intensity of culling of cows in terms of the lactation and the year of removal from the herd,
• the length of life, productive life, the number of milking days and lifetime productivity of cows in terms of the year of removal from the herd,
• the length of life, productive life, the number of milking days and lifetime productivity of cows in terms of the cause for culling.

The culling index for cows in the investigated period was 28.18%. A increase was found in this index in successive years of the study from 23.82 (2001) to 36.18% (2003). In the analyzed years cows were removed from the herd with highest intensity due to sterility, casualties and low yields. The highest culling index was found for cows in the second lactation. As a result of the conducted analyses it was shown that cows kept in the free barn system were characterized by a too short life and productive life, while their lifetime productivity expressed in kilograms of milk, butterfat and protein was relatively high. Statistical analysis did not show differences between the lengths of life for cows removed from the herd for the above mentioned reasons. In contrast, it was found that animals culled due to these causes differed in the length of their productive lives and the number of milking days. The least advantageous values of the analyzed traits of milking performance were found in the group of cows culled due to sterility and casualties.

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