EN
1283 cows of black-white lowland breed kept on state farms in the areas of various pollution degree were studied. Three groups of herds were distinguished according to the degree of pollution: the cows following the first lactation, the cows that began their milk production in 1973-80 and culled in 1974-84. The following data were determined for each cow: the age of the first calving, the lenght of performance, life time and life yield. Moreover, the reasons of culling were determined as well. It has been found that in all polluted areas the lenght of life and performance is too short. The cows kept in the most polluted area have the shortest time of performance / 3,16 y/. The cows beginning their milk production in 1977-80 had the shortest life time and performance. In those cows, the age of the first calving tended to increase. The cows kept in the most polluted area had the lowest milk and fat yield /9075 kg and 373,7 kg respectively/. Barrennes was the most frequent reason for culling in all the herds studied.