TY - JOUR AU - V. Prishedko AU - E. Lesnоvskay AU - L. Karlova AU - V. Dutka PY - 2017/10/30 Y2 - 2024/03/29 TI - Economic efficiency of the use of using the first-born cows of Holstein breed with different intensity of their formation in early ontogenesis JF - Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies. Series: Agricultural sciences JA - nvlveta VL - 19 IS - 79 SE - Articles DO - UR - https://nvlvet.com.ua/index.php/agriculture/article/view/2801 AB - The increase in milk productivity is indissolubly related to the production economy, as the payment of food for dairy products is directly dependent on the volume of the dairy. The aim of the research was to establish the economic efficiency of using the first-born cows of Holstein breed with different intensity of their formation in early ontogenesis. Experimental heifers significantly differed in development, both at the beginning and at the end of their breed. By the size of the live weight, the heifers and the experimental group dominated the elders with a high degree of confidence in the difference. At 6 months of age, the difference was 16.90 kg (10.40%), 12 months – 19.85 kg (7.07%) and 18 months – 21.75 kg (5.79%). Absolute gain for the period 0–6 months  in the first group was 17.15 kg more than in the second and was 153.75 kg. In the periods of 6–12 and 12–18 months, no reliable difference was found for this indicator. The analysis of average daily gains of experimental animals showed that the heifers of the first group for this indicator faithfully prevailed in the age groups of 0–6 and 0–18 months, respectively: 95.3 g (12.6%) and 40.7 g (6,4%). Average daily gains at the age of 6–12 and 12–18 months  in the heifers of groups I and II did not significally differ. The analysis of the milk productivity of the first-breed cows at different intensities of formation showed that the first-breed cows, which had higher daily average gains, were significantly superior to those of the same age with a lower intensity of formation of 1093.0 kg (28.06% for P > 0.999). The fat content of milk in experimental animals was not significantly different. Animals of the first group were characterized by high milk productivity.  Their milk yield for the fitst lactation amounted to 4988.5 kg, up to the second lactation it increased by 222.1 kg (4.5%), from the second to the third lactation by 304.0 kg (5.8%), and in general from the first to the third – by 526.1 kg (10.5%).  The milk productivity the first-breed cows of the second group was 3895.5 kg, the increase in the supply of the second lactation amounted to 906.3 kg (23.3%), productivity growth from from the second to the third lactation was 376.7 kg (7.8%), in the period from the first to the third lactation in this group, the overall increase in fertility increased by 1283.0 kg (32.9%). The rate of formation of primary cows in early ontogenesis of cows more affects the pulse rate and rectal body temperature and is less in the frequency of respiratory movements. In the first-born cows with a fast intensity of formation compared with analogues with a slow intensity of formation, a tendency towards higher rates of pulse and respiratory movements at a lower rectal body temperature have been observed. During conducting the correlation analysis of the relationship between the live weight at different ages of the first-born cows and the content of fat in milk we have been revealed a positive average power of a reliable relationship between live weight at the age of 6 and 18 months with the tardiness of the first lactation.  The relationship between live weight and fat content in milk was weak and unreliable. From the the first-born cows with a rapid intensity of formation, in comparison with the first-borns with a slow intensity of formation, more milk was extracted at a cost of 9890.6 UAH.  (on 100 heads – 989060,0). Calculated indicators of economic efficiency prove the expediency of selecting cows, not only on the indicators of dairy productivity, but also on such indicator as the intensity of the formation of the heifers up to 18 months of age.  In this case, it is necessary to take into account the average daily increment of live weight of heifers, which in the future can ensure the maximum profit of the milk industry. ER -