Fat and protein content in milk of Black and White breed cows imported to Poland and their dams kept in Holland

Values of milk traits during the first lactation of Black and White cows im ported from Holland and Poland were significantly higher in comparison to t heir dams:+ 4.4* milking days, milk yield + 505kg, **total fat and protein yield + 35.1 kg*, milk fat content + 0.06% and the difference between % fat and protein contents (RTB) was lower by 0.17%". However, daughters were ch aracterized bp lower Values of milk protein content by 0.00%** and protein : fat (SBT) ratio milk by 0.3*, when compared to their dam's performance in Holland. Nearly half of the:cow population imported from Holland (48.5 %) produced milk with a fat-content above 4.4%, while only 34.5% of the dam po pulation reached this level, In case of high protein content in milk (> 3.4 %), there were twice as many dams included in this subgroup, (62.1%) than t heir daughters (28.8%).:Relations between milk performance:indices were mor e favourable in dams kept in Holland (SBT: 0.72-0.85; RTB: 0.57-1.04%) than in daughters kept in Poland (SBT 0.72-0.86; RTB: 0.85-1.3%).