Influence of Live Weight, Age of First Insemination and Calving on Milk Productivity of Cows

Abstract

The article examines the influence of live weight, age of first insemination and calving on the milk productivity of cows of the Ukrainian red-spotted dairy breed in the conditions of LLC "ATZT Myrne" of the Kitsman district of the Chernivtsi region. The milk productivity of first-born cows largely depends on their live weight, because it is an indicator of the general development and fattening of animals. The results of our research indicate the influence of live weight of animals on their milk productivity. When the live weight of animals at the first insemination increases from 300 to 450 kg, the yield increases by 699.3 kg, milk fat by 28.9 kg, and milk protein by 25.2 kg (P<0.05, P<0.01). The influence of live weight at the first insemination on fertility, the amount of milk fat and protein was 15.1-19.1 %. When studying the dependence of the milk productivity of first-borns of the Ukrainian red-spotted dairy breed on the age of their first insemination, it was established that the cows with the age of first insemination ranged from 16.1 to 18.0 months had the highest fertility, the amount of milk fat and protein. – 6875.8, 266.6, 227.1 kg, respectively (P<0.05). The influence of the age of first insemination on fertility, the amount of milk fat and protein was 5.7-9.5 %. According to the results of own research, it was established that the live weight of first-born cows at the first calving affects their milk productivity. With an increase in live weight to 550 kg, their weight increases by 312.9 kg, milk fat by 11 kg, and protein by 10.8 kg. With an increase in live weight of more than 551 kg, the productivity of cows does not increase, but remains at a high level - 6682.7 kg, 257.1 and 220.1 kg, respectively. Correlation coefficients between live weight at the first calving of cows and their productive indicators were -0.072-0.113. A significant influence of the live weight of the firstborns at the first calving on their fertility, the amount of milk fat and protein (15.3-22.9 %) was established, which proves the need for intensive breeding of repair young. It has been established that the age of first calving of first-born cows affects their future milk productivity. Cows with the age of first calving in the range of 25.1-27.0 months had the highest hope, amount of milk fat and protein. – 6510.2, 252.3 and 217.0 kg, respectively (P<0.05). First-borns with the age of first calving of 29.1–31.0 months were characterized by the lowest indicators of milk productivity. Their weight was 6017.2 kg, the amount of milk fat and protein was 234.7 and 198.6 kg, respectively (P<0.05). The correlation coefficients between the age of the animals at the first calving and their milk productivity were in the range of -0.088–0.240. The influence of the age of the first calving on fertility, the amount of milk fat and protein was 20.7-23.6 %.