GROWTH AND DEVELOPMENT OF REPAIR HEIFERS OF UKRAINIAN BLACK-AND-WHITE DAIRY BREED OF DIFFERENT TYPES OF CONSTITUTION
Authors: Dynko Y. P. 
Published: November 2018

The features of growth and development of Ukrainian Black-and-White Dairy heifers of different constitution types were investigated in the article. The study was conducted in 2016 in the breeding farm APC named after Shchorsa, Kyiv region (n = 109). Differentiation of cows on constitution types was conducted by the methods proposed by O. M. Chernenko and N. N. Kolesnik.

According to the classification of O. M. Chernenko distribution of first-calf cows by constitution types was as follows: big-capacity type – 75 %, mid-capacity – 16 %, low-capacity – 9 %; according to the classification of N. N. Kolesnik – wide-body type – 56 %, narrow-body type – 44 %.

Advantage for most body measurements was in first-calf cows with big-capacity type which prevailed over the low- and mid-capacity type animals by height at withers by 2.9 and 0.9 cm, respectively, chest girth – 6.6 cm and 5.0 cm (P < 0.05). Advantage over low-capacity type by width and depth of chest behind the blades, width and depth of chest behind the last rib and the length of thoracic was 4.9 cm, 4.4 cm, 7.0 cm, 7.3 cm and 3.7 cm, respectively (P < 0.01 in all the cases). It was found the significant advantage for the metacarpal girth of big-capacity type animals over mid-capacity type animals – 0.5 cm (Р < 0.01). The first-calf cows with narrow-body type of constitution had advantage over wide-body type on such measurements: height at withers – by 1.3 cm, chest girth – 4.9 cm (P < 0.01), depth of chest behind the blades – 0.9 cm, depth of chest behind the last rib – 0.8 cm, width between pin bones – 0.9 cm, sloped body length and metacarpal girth – by 0.3 cm. The first-calf cows with wide-body type had advantage for width of chest behind the blades – by 2 сm (P < 0.01), width of chest behind the last rib – 3.1 сm (P < 0.01), length of thoracic – 0.6 cm and width between hips – by 2.9 сm (Р < 0.001).According to the classification of O. M. Chernenko the significant advantage only was found for long-leg index in animals with low-capacity type over big-capacity type – by 2.1% (P < 0.01). The animals with wide-body type of constitution compared to narrow-body type (according to N. N. Kolesnik) predominated by wide rear, long-leg, stretching and thoracal indexes by 2.4% (Р < 0.01), 0.2%, 0.7% and 3.4% (Р < 0.01), respectively. The first-calf cows with narrow-body type of constitution predominated for pelvic-breast index by 2.0%, compactness index – 3.1%, boniness index – 0.2% and narrow rear index – by 6.6% (Р < 0.001).It was found that the highest live weight from 3 to 18 months had heifers with mid-capacity type of constitution. The first-calf cows with mid-capacity type of constitution predominated over the first-calf cows with big-capacity type at 3 months’ age by 7.6 kg (Р < 0.05), the advantage over low-capacity type was 6.9 kg. Heifers with mid-capacity type of constitution at age of 6, 9, 12, 15 and 18 months compared to other groups had live weight by 13.8–18.6 kg, 16.7–23.2 kg, 11.4–29.3 kg 5.1–28.2 kg and 12.8–20.1 kg higher, respectively.It was found that live weight of newborn heifers with narrow-body type was significantly higher by 1.2 kg (Р < 0.05). Significant differences of live weight from birth to 18 months between replacement heifers with narrow- and wide-body types of constitution were not found; the difference varied within 0.5–3.3 kg depending on the age of the animals. Live weight during the first insemination of heifers with wide-body type was higher by 17.1 kg, but the difference was insignificant.The heifers with mid-capacity type of constitution had the advantage over the other by the absolute gain from birth to 3 months – 9 kg (P < 0,01), low-capacity type – 6 kg. Also the heifers with mid-capacity type were characterized by the highest absolute gain in periods of 3.1–6.0 months and 6.1–9.0 months, that 6.1–11.7 kg and 2.9–4.6 kg higher compared with heifers of other types of constitution. In periods of 9.1–12.0 and 12.1–15.0 months the highest absolute gain was in animals with big-capacity type of constitution – 69.8 kg and 69.2 kg, respectively.Regarding absolute gain from birth to 18 months significant differences between the repair heifers of wide- and narrow-body types of constitution weren’t found, the differences varied within 0.1–3.8 kg.The highest relative gain of live weight in periods of 0–3.0 and 3.1–6.0 months was observed in heifers with mid-capacity type of constitution – 206.2% and 72.8%, respectively. The relative gain of heifers in period of 6.1–9.0 months varied within 41.8–42.8%. In periods of 9.1–12.0 and 12.1–15.0 months heifers with big-capacity type had 3.9–4.3 % and 1.2–3.0 % higher relative gain compared to heifers with other types of constitution. In period of 15.1–18.0 months heifers with mid-capacity type of constitution predominated over animals with big-capacity type by the relative gain – 2.4 % (Р < 0.01).

The difference of relative gain between the narrow- and wide-body types of constitution was 0.2–5.8 %, depending on the age period.

The heifers with mid-capacity type of constitution significantly prevailed over heifers with big-capacity type by daily gain by 100 g (Р < 0.01) at the age of 0–3.0 months, the advantage over animals with low-capacity type was 67 g. At the age of 3.1–6.0 and 6.1–9.0 months daily gain of heifers with mid-capacity type was 29–68 g and 32–51 g higher compared to animals of other types. The heifers with low-capacity type significantly prevailed over heifers with big-capacity type at age of 15.1–18.0 months by 182 g (Р < 0.05).

Significant differences for live weight and live weight gain between first-calf cows with wide- and narrow-body types weren’t found.