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UDC 636.2.034.082.26

Received: May 12, 2026

Revised: May 20, 2026

Published: May 29, 2026

This is an Open Access article under the CC BY-NC-ND 4.0 license

 

The article presents the results of studies on the influence of the month of the year and the season of birth on the bode weight gains of replacement heifers. The temperature and humidity index (THI) was used to characterize the heat load.

The influence of the month of the year on the monthly gain in the SE RF “Myrne” was 5.9%, and in the SE RF “Stepne” – 7.4%, while on the average daily gain – 5.4% and 7.1%, respectively (p < 0.001). In the first farm, the smallest monthly gain of replacement heifers was obtained in February and March, and the smallest average daily gain – in March. The largest gains were observed in January. The difference between the mean values was 5.1 kg and 184 g, respectively. In the second farm, the smallest monthly gain of replacement young stock was obtained in February, and the smallest average daily gain – in January, February and March. The differences between the mean values were 6.7 kg and 203 g, respectively. According to the results of the Tukey a posteriori criterion, the differences between the indicated groups were significant.

The influence of the season of heifer birth on the gains in the SE RF “Myrne” was 0.6%, and in the SE RF “Stepne” – 1.3% (p < 0.001). In the SE RF “Myrne” the smallest monthly and average daily gains were obtained in replacement heifers born in the fall, while the largest values of these indicators were obtained in animals born in the winter. The difference between the average values was 1.4 kg and 48 g, respectively. In the SE RF “Stepne” the smallest monthly and average daily gains were obtained in replacement young animals born in the spring, and the largest – in animals born in the summer. The differences between the average values were 3.1 kg and 100 g, respectively. Tukey’s a posteriori criterion indicates the probability of differences between the groups.

 

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