There are various methods for determining the type of constitution of dairy cattle, that’s why study the features of the udder development and milk production of cows depending on the constitution is a key issue.

The study was conducted in 2016 on the breeding plant VCA named Shchorsa, Kyiv region (n = 101). Differentiation of cows on constitution types was conducted by the method proposed by O.M. Chernenko (big-capacity type, mid-capacity type, low-capacity type) and N.N. Kolesnik (by mass index – loose-tight, bone index – tender-rough, wide-rear and wide-thoracal indexes – narrow-body and wide-body).

According to research results, by massiveness index was found a small advantage of udder measurements of loose type constitution heifers compared to tight on 0.1–1.3 cm, but the advantage was significantly only teats length – 0.3 cm (P<0.05).

Cows of loose type constitution also were characterized by higher values of the index format – 1.1 % (P<0.05), the relative size of the udder – 0.3 % and the notional value of the udder – to 122.6 notional units, only the index of relative value was less on 0.8 %. The difference of udder measurements of tender and rough types constitution heifers (by boniness index) was within 0.1–3.6 cm, except for length and diameter of the teats, which are equal to 5.5 cm and 2.3 cm, respectively, for both types of constitution.

By the length, width, depth and girth of udder and the distance between the front and rear teats the cows of rough type’s had advantage, but in all cases it was not significantly. Heifers of tender type’s constitution had advantage by the distance from the bottom of the udder to the floor on 3.6 cm (P<0.01). Higher index values udder (size, relative size and relative size) and notional values of udder observed in cows of rough-type’s constitution – on 0.5–1.0 % and 130.3 notional units, respectively, compared to peers of tender type.

For the wide rear and wide thoracal indexes was found advantage cows of wide-body type’s over narrow-body type’s cows by the udder length (on 1,5 см, Р<0.05) and the distance between the rear teats (0.5 cm). The narrow-body type’s cows had advantage by the other udder measurements but the difference was the improbable and varied within 0.1–2.0 cm, except the distance between the front teats, which in both cases was 12.1 cm. By udder index the difference between cows of narrow-body and wide-body type’s were not found.

According to the classification of O.M. Chernenko cows of big-capacity type constitution compared with low- and mid-capacity types, had the advantage by the udder depth (on 0.9–1.0 cm) in length and diameter teats (on 0.4–0.5 cm and 0.1 cm, P<0.05, respectively). The advantage of these measurements led to higher index values format (by 1.1–1.3 %) and the notional value of the udder (in 64.9–96.6 notional units).

Heifers of low-capacity type of constitution, compared to mid- and big-capacity types, characterized by longer udder (in 2.1–2.5 cm) with a larger girth (by 1.3–2.7 cm) and the highest value index of relative value (on 3.7–3.9 %). However, cows of low-capacity type had the shortest distance between the front and rear teats (by 0.1–0.2 cm 0.1–0.9 cm, respectively) and distance from the bottom of the udder to the floor (5.5–5.8 cm) and the smallest length teats (at 0.1–0.5 cm).

Therefore, according to the classification of N.N. Kolesnik, the advantage for most measurements and indexes of udder observed in loose heifers (massiveness index), rough (boniness index) and narrow-body type of constitution (wide rear and wide thoracal indexes). According to the classification by O.M. Chernenko type of constitution clear trend depending between measurements and indices of udder from the type of constitution udder were not found.

Analysis of milk production of heifers during 100 days of lactation showed that classification by N.N Kolesnik is the most informative for determining the type of constitution was boniness index (tender-rough types). Cows of rough-type constitution characterized by the highest yields (+225 kg), the amount of milk fat (+7.9 kg) and milk protein (+7.0 kg), compared with a tender type, but in all cases the difference was the improbable. Among the types of constitution loose-tight and narrow- and wide-body difference in indicators of milk production was not much: for milk yield – 18–40 kg, the amount of milk fat – 0.8–1.3 kg milk protein – 0.7–1.3 kg, the highest daily milk yield – 0.3–1.7 kg. For the milk advantage of fat and protein in milk differences depending from the type of constitution were not set.

Distribution heifers by the types of constitution by O.M. Chernenko showed that higher levels of yield, the amount of milk fat and milk protein, and highest daily milk yield had cows of big-capacity type. Compared to the low-capacity type of constitution cows of big-capacity type for 100 days of lactation was higher yield on 403 kg (P<0.05), the amount of milk fat – 13.3 kg (P<0.05), milk protein – 12.3 kg (P<0.05) higher daily yield – 3.2 kg (P<0.05). The advantage over peers such mid-capacity type of constitution was, respectively, 101 kg, 3,6 kg, 3,1 kg and 2,3 kg. Slightly higher the milk fat advantage of cows observed in low-capacity type’s cows.

Thus, the classification types of constitution of cows proposed O.M. Chernenko is more informative to determine the desired type of constitution. It was established that the firstborn of big-capacity type had the higher yield, the amount of milk fat and milk protein and the higher daily yield (P<0.05 compared to the low-capacity type).

According to the results of variance analysis, in the herd of VCA named Shchorsa impact strength of type’s constitution to indicators of milk production of cows ranged between 0.6–39.3 %. The impact strength of constitution types, classified by M.M. Kolesnik, examined indicators of milk production was weak and improbable (η²_x = 0.6–3.5 %). The impact of the type of constitution firstborn, classified by O.M. Chernenko, their milk production was higher (η²_x = 8.8–39.3 %) and significantly for milk yield (η²_x = 39.3 %, P<0.05), the amount of milk fat (η²_x = 28.1 %, P<0.01) and milk protein (η²_x = 33.3 %, P<0.01) and higher daily milk yield (η²_x = 24.3 %, P<0.05).

Thus, the method of classifying types of constitution affects the results of the assessment cows for udder development and milk production. Classification proposed by O.M. Chernenko is more informative to determine the desired type of constitution of cows.

Key words: Ukrainian Black-and-White dairy breed, types of constitution, measurements and indices of udder, milk production.