Utjecaj nehranidbenih čimbenika na razinu uree u mlijeku i njezina povezanost s parametrima mliječnosti i plodnosti u mliječnih stada u Vojvodini

The purpose of this study was to examine possible relationship between milk urea and fertility of dairy cows using field data. This study also evaluated the influence of environmental factors on milk urea (MU) and the relationship between MU and daily milk yield, milk fat and protein percentage. The data were collected at 11 dairy farms in the Vojvodina region. Reproductive dana and MU measurements were obtained from cows that calved between June 2013 and October 2015 and had a successful conception after calving. Statistical data processing was carried out by applying General Linear Model procedure, Statistics 13. Parity, calving season, season of milk control and farm were included in the models as fixed effects. Significant differences in MU concentrations were observed between farms (P35 mg dL-1 imale najdulje servisno razdoblje (163,18 dana). Nadalje, krave s najnižim prosječnim MU vrijednostima (