REPRODUCTION RATES OF COWS AND HEIFERS KAMYSHENKA LLP OF AKMOLA REGION
Keywords:earlier insemination, reproduction rates, milk production, high productive cows, first calving cows, heifers, insemination index, live weight, blackmotley breed, Simmental breed.
The studies have shown that in both breeds, while the insemination of heifers at an earlier age, animals had a higher level of productivity, so high-producing cows were inseminated at the age of 18 months, while cows below average in productivity in the
herd were inseminated at 20-21-month age. Live weight during insemination at an early age in black-motley breed heifers in highly productive cows was 346 kg, and in Simmental breed is 356 kg, which is 65-70% of the breed standard. The insemination index in heifers at an earlier age was 1.2, and in the heifers inseminated at an older age was 1.8. However, the correlation coefficient between the milk yield and the first insemination age, being positive, was insignificant, while the correlation coefficient between the milk yield and live weight was medium positive in the black-motley breed, while with an increase in live weight of Simmental heifers milk yield is reduced, so they moved from the milk into meat type, which is a negative indicator for dairy farms. As recommendations, the farm was offered to inseminate no later than at the age of 18 months and with 340 kg live weight in heifers of black-motley breed and 350 kg in Simmental breed. However, for this it is necessary to apply the intensive technology of growing repair heifers, where the main attention is paid to achieving breeding live weight at an earlier age.