Breeding efficiency of agricultural animals increases significantly when a selection between two signs are positive coupling variability. With a high degree of correlation between the two traits, selection on one of them increases the other related signs. Scientists experimentally found a positive relationship between exterior-constitutional peculiarities and productivity of dairy cattle.

Based on the analysis of milk productivity indices and measurements of the body it is established that with increase of the measurements of heifers Ukrainian Black and White dairy breed, there is a tendency to increase the value of milk yield for 305 days of lactation, milk fat and milk protein.

In cows with height at withers 142 cm and greater  milk yield was higher on 1025 kg, than in cows with height at withers 135 cm or less, the advantage of cows with height at withers 142 cm or more with the amount of milk fat was 36 kg (P < 0,05), the number of milk protein – 32 kg (P < 0,05). However, heifers with a height at withers of 135 cm and had less long lactation period of 446 days. The advantage over animals of other groups were 10–36 days. Mass fraction of fat in milk, depending on the height at the withers, ranged from 3.49–3.51 %, mass fraction of protein was present at a level of 3.10 % in all groups.

Cows with depth of chest 76 cm or more had a higher milk yield for 305 days of lactation and the greatest amount of milk fat and milk protein. The advantage over the heifers with the depth of the chest 71 cm and less were: yield – 1863 kg (P < 0.01), for the amount of milk fat – 65 kg (P < 0.05), for the amount of milk protein – 57 kg (P < 0.01); cow with depth of chest 72–73 cm and 74–75 cm dominated by 0.02 % when the mass fraction of fat in milk. A somewhat higher mass fraction of protein had heifers with depth of chest 74–75 cm to 3.11 %, which is 0.01–0.03 % more in comparison with animals of other groups. Length of lactation period ranged from 384 to 455 days, however, certain tendencies depending on the depth of the chest was found and the difference was not reliable.

Cows with oblique body length 165 cm and more dominated by peers with oblique body length 156 cm and less yield at 1268 kg (P > 0,05), milk fat – 45 kg (P > 0,05), milk protein – 40 kg (P < 0,05). The highest mass fraction of fat in milk had animals with oblique body length 157–160 cm and 161–164 cm – of 3,51 %, which were superior to cows in the other groups by 0.02 %. A somewhat higher mass fraction of protein in the milk had a cow with oblique body length 161–164 cm. Advantage over peers was 0.01 to 0.02 %. Heifers with oblique body length 157–160 cm was characterized by a longer lactating period (25–37 days), compared with cows of other groups.

In the studied herd of cows with a chest girth of 198 cm and more dominated by peers with a smaller chest girth  for the milk yield of 305-day lactation , amount of milk fat and milk protein. The advantage in yield over the animals with a chest girth of 189 cm and less was 979 kg, for the amount of milk fat and milk protein – 35 kg and 32 kg, respectively (P < 0.05). The mass fraction of fat in milk ranged from 3.50−3.51 %, mass fraction of protein was equal in all groups – 3.10 %.

In the herd of Shchorsa VCA metacarpus girth 16 cm had 49 heifers, 17 cm – 44 the heifers, which accounted for 93 % of the investigated group. As a result of own research were found the advantages of the cows with the metacarpus girth 17 cm above the peers with the metacarpus girth16 cm for the milk yield of 305-day lactation (579 kg), for the amount of milk fat (20 kg) and milk protein (18 kg). Cow metacarpus girth 17 cm was shorter at 27 days of lactation period.

So, Therefore, in the herd of Shchorsa VCA the highest milk yield for 305 days of lactation, the amount of milk fat and milk protein obtained from heifers that had more measurements of the body: height at withers 142 cm, depth of chest – 76 cm, oblique body length – 165 cm, chest girth 198 cm or more, metacarpus girth 17 cm. The advantage in most cases was likely.

Established positive relationship between body measurements and 305-day lactation yields, amount of milk fat and milk protein gives the grounds to assert about the effectiveness of indirect selection of heifers in terms of exterior.

Force measurements of the body on the indices of milk productivity of heifers of the Ukrainian black and white dairy breed varied from 0.6 to 33.2 per cent. The likely impact on milk yield for 305 days of  lactation, amount of milk fat had the depth of chest (η²_x = 37,6% and η²_x = 20,2 %, respectively, P < 0,05 in both cases), and the number of milk protein – slanting length of body (η²_x = 23.6 %, P < 0.05).

Key words: Ukrainian Black-and-White dairy breed, milk production, measurements of the body, correlative variability.