Analysis of milk characteristics of cows and their daughters

Milk yields of 43 419 Black-White and 20 995 Red-White cows and their daugh ters used in 1978-1993 in the South-West region of Poland were analysed. Br eeding values of all animals were estimated by BLUP (Animal Model). The dat a was preadjusted for age and season of calving. Cows-dams were classified to a group of cows with high performance by two ways: 1. cows recorded in H igh Performance Register, 2. cows which exceeded an assumed production leve l ((x) over bar +1.96 s, 1.64 s or 1.28 s, respectively). Breeding values o f classified dams were higher than those of remaining dams. Similarly, daug hters of these darns had higher breeding values than daughters of remaining dams. Greater differences were observed in Black-White breed. Generally, d ifferences of breeding value in dam group were higher than in daughter grou p.