PECULIARITIES OF DEVELOPMENT OF UKRAINIAN REPAIR HEIFERS RED-AND-WHITE AND BLACK-AND-WHITE DAIRY BREEDS IN FARMS OF SUMY REGION

The leading farms of the Sumy region studied the peculiarities of the growth of repair heifers of Ukrainian Black-and-White (PZ PE "Burynske") and Red-and-White (LLC "Mlynivskyi complex") dairy breeds. The absolute and relative indicators of live weight gain of heifers in the age dynamics from birth to 18 months of age were studied. Heifers of the Ukrainian Red-and-White dairy breed (36.2 kg) were the best in terms of live weight at birth in comparison with the peers of the Ukrainian Black-and-White dairy breed (33.9 kg). Their advantage persisted during the 18-month growing period. Repair heifers of the Ukrainian Red-and-White dairy breed at the final stage of development with an average live weight of 414.2 kg exceeded the peer of the Ukrainian Black-and-White dairy breed with a highly reliable difference of 15.5 kg (P <0.001). The development of repair heifers of both breeds within the obtained live weight indicators ensured their increase at the time of mating age at the level of 76-80% of the minimum target standards set for the first-born cows of dairy type of the created breeds. The average daily gains in live weight in the milk period averaged 810.4 g in heifers of the Ukrainian Black-and-White dairy breed, and 847.3 g in their peers of the Ukrainian Red-and-White dairy breed, the highest in the animals of the Ukrainian Red-and-White dairy breed herd LLC "Mlynivsky complex". The results of research showed that with the creation of appropriate conditions for feeding and keeping repair heifers of Ukrainian Black-and-White and Red-and-White dairy breeds were capable of high growth intensity.