The study was carried out in 2006–2011 in a farm located in the Kujawsko-Pomorskie province and keeping about 290 Polish Black-and-White Holstein-Friesian cows with a mean yield of almost 11,000 kg milk. GLM and FREQ procedures of the SAS package were used for statistical analysis. The lifespan and length of productive life of high-yielding cows tended to decrease, with an alarming tendency for the increasing proportion of cullings among young cows, especially in the first lactation. Culling intensity was found to be high (32%). The proportion of voluntary culling decisions by the breeder, which include selling for further breeding, low productivity and old age, decreased from about 6% in 2006–2007 to about 2% in the following years. High-yielding cows were mainly culled for infertility and reproductive diseases (35.9%), diseases of the locomotor system (15.1%), udder diseases (13.1%), and metabolic and digestive diseases (12.9%).

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