The study has found out that milking duration was 5.59–5.96 min under the amount of 29,8–30,6 kg daily milk yield in 1st lactation foreign selection cows, including one-time milking of 9.9–10.6 kg. Milking duration of Ivano-Frankivsk selection cows, compared to the duration of milking their peer cows of Hungarian, Danish and German selection was correspondingly lower by 0.38; 0.14 and 0.01 min, which corresponded their daily yields. Regarding the duration of milking cows of Agrosvit Ltd., this index is dominated in the peers of Danish and German selection by 0.16 and 0.29 min respectively, but in Hungarian breed cattle the duration was only 0.08 min shorter.

Regarding the assessment of twice calved cows milking duration, they were evidently adequate to the average daily yields. For example, milking duration in the Hungarian selection cows was 6.37 minutes for a daily milk yield of 33.1 kg, including single milking of 12.3 kg, versus 5.92 minutes duration for the daily milk yield of 32.8 kg (11.2 kg single milking yield) in German Holstein selection. In Danish selection cows milking duration occupies an intermediate position of 6.32 min under the daily milk yield of 32.6 kg. Ivano-Frankivsk selection cows were almost on a par with the German selection cows by the duration of milking – 5.96 vs. 5.92 min, but inferior to Hungarian and Danish selection cows, by 0.41 and 0.36 min, or 6.9 and 6.0% (P<0.95) respectively.

Cows of Agrosvit Ltd. selection were almost the same as the German selection cows by milking duration – 6.01 vs. 5.92 min, and 0.36 and 0.31 min, or 6.0 and 5.2% (P<0.95) respectively lower as compared with the duration milking Hungarian and Danish selection cows. In general, it can be noted that both average daily yields and milking duration of 2nd lactation cows of domestic and foreign selection did not differ significantly from each other, except for the Hungarian selection cows.

3rd lactation analogue cows of foreign selection, particularly Hungarian, Danish and German ones, did not differ much from a biotechnological index of milking duration which were close to daily (30.5, 29.8 and 30.2 kg) and one-time (10.3, 9.9 and 10.2 kg) yields. For example, it was the longest in Hungarian selection cattle – 5.69 min, only 0.16 minutes, or 2.9 %, less in Danish selection cows, and in German selection cattle, by contrast, it was only 0.07 minutes, or 1.2 % slower.

Regarding the duration of milking 3rd lactation analogue cows of domestic selection, it did not differ significantly from foreign selection animals under slightly lower daily milk yield (28,9–29,4 versus 29,8–30,5) though it was clearly higher. Thus, in cows of Ivano-Frankivsk selection under single milk yield of 9.8 kg, milking duration was longer than in the cattle of Hungarian, Danish and German selection, by 0.18; 0.34 and 0.11 min, or 3.2; 6.1 and 1.9 % (P<0.95) respectively; in cows of Agrosvit Ltd. under single milk yield of 10.1 kg it was respectively by 0.15; 0.31 and 0.08 min, or 2.6; 5.6 and 1.4 % (P<0.95) longer.

With respect to the average milking yield intensity, 1st lactation cows of domestic selection, it was almost on a par with foreign selection cows – 1.73–1.76 versus 1.77–1.80 kg per minute. The same is true for maximum milking intensity – 3.56–3.65 versus 3.77–3.97 against kg per min and the values of manual milking (40–42 vs. 32–39 ml).

Medium and maximum milking intensity in 2nd lactation cows of national selection hardly differed from that of their peers of foreign selection. In particular, the average milking intensity in domestic breeding cows was 1.81–1.83 versus 1.82–1.93 kg per min in foreign selection cows, maximum milking intensity was, respectively, 3.86–3.90 versus 3.97–4.17 kg per min.

With regards to the average milking intensity, 3rd lactation cows of Agrosvit Ltd. were inferior to their peers of Hungarian, Danish and German selection, by 0.08; 0.06 and 0.04 kg per min or 4.6; 3.5 and 2.3 % respectively and the difference in terms of maximum intensity was respectively 0.23; 0.09 and 0.21 kg per min or 6.4; 2.5 and 5.9 % (P<0.95).

Thus, a comprehensive assessment of the data can reveal that the cows of domestic selection Holstein breed are well adapted to loose-boxed farming conditions and practically they are not inferior to their foreign selection peers by adaptation to machine milking.

Key words: high yielding Holstein breed cows of foreign and domestic selection, adaptation to machine milking.