REPRODUCTIVE PERFORMANCE AND QUALITY OF THE PROGENY OF COWS IN THE CONDITIONS OF SARYAGASH LLC, KOSTANAY REGION

Abstract

This study presents the results of monitoring the reproductive performance of Holstein cows at LLP «Saryagash», Denisov District, Kostanay Region. The general reproductive health of the herd complies with zootechnical requirements, ensuring high offspring survival. The age structure was favorable: 70.5% of cows belonged to the 2nd–3rd calving groups, while older groups represented only 2.2%. The average age at first calving was 24–26 months, with a significant deviation observed in Group 5 (35±11.91 months).

The mean semen use per successful insemination was 3.29±0.41 doses, with heifers requiring 2.94 doses. Group 2 showed the most favorable results (9.12% below the herd average), while older groups demonstrated increasing insemination numbers, peaking in Group 6 (+21.5%). The average service period was 177.24±79.54 days, longest in Groups 3 and 6. Parturition generally occurred without complications; abortion and assisted calving rates did not exceed 0.4%.

Calf birth weights varied by calving number: highest in Group 2 (+1.9% vs. average) and lowest in first-calf heifers (–2.3%). The findings confirm high reproductive efficiency in the herd, though certain technological stages require improvement.