Red and White Lowland breed of cattle (Rotbunt) in Vojvodina province [Yugoslavia] (3)
1989
Nenadovic, M. (Poljoprivredni fakultet, Beograd (Yugoslavia)) | Antov, Dj. ("Servo Mihalj", Zrenjanin (Yugoslavia). "Zrenjanin")
The effect of bull sires on the variability of the analysed characteristics was significant, highly significant or very highly significant in all cases except the durations of lactation and pregnancy. These results were obtained on the basis of the analysis of variance and the F-test. The values of the heritability coefficients (h2) for the characteristics of milkiness in the first lactation ranged from 0.007 (for the duration of the first lactation) to 0.544 (for the milk yield in the first lactation to 305 days). Among the analysed reproduction characteristics, the lowest value of h2 was found for the duration of pregnancy (h2=0.081) and the highest for the age at the first conception (h2=0.510). Among the analysed longevity characteristics, the values of h2 were less variable, ranging from 0.188 (for the number of lactations) to 0.243 (for the number of milking days in the lifetime). The values of heritability for the total yield in the lifetime were 0.218 for milk yield, 0.293 for fat yield and 0.532 for fat content. The values of heritability for the average milk yield per day were 0.450 for production day, 0.265 for lifetime day, 0.226 for milking day and 0.175 for the part of production lifetime. Since the portion of additive genetic component of the sires in the total phenotypical variance was mostly high and frequently very high, it was concluded that the analysed herd may be successfully bred for the characteristics studied in this investigation.
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