An analysis of some factors affecting the milk production of cows sired by Montbeliarde sires in the Czech Republic
2001
Chladek, G. | Kucera, J. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Ustav Chovu Hospodarskych Zvirat)
The data set consisted of first lactation records from 1928 cows sired by 46 Montbeliarde bulls. Dams of the cows under observation in this study were either Montbeliarde (n=922) or Czech Spotted cows (n=1006). The mean production of the whole population was 4586.9 kg of milk and 155.9 kg of protein per lactation, with the protein content 3.29 %. Factors analysed for their effect on protein production included sire, breed of the dam, age at first calving, year of calving, season of calving, and herd. Analysis revealed that the model including the effects of sire, dams breed, age at first calving, year of calving, season of calving and herd explained the largest proportion of explained variance in protein production. In all models, effect of sire, age at calving, year of calving and herd were always significant whereas the effects of dams breed and season of calving were not always significant.
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