Non-Genetic Factors Affecting Milk Yield, Composition and Somatic Cell Count in Hungarian Holstein Cows
Özet
The purpose of this study was to determine effects of non-genetic factors on milk yield, milk composition and somatic cell count (SCC) of dairy cows. A total of 4891 records of Hungarian Holstein cows raised in a private dairy farm in South Hungary, between 2007 and 2008 were investigated. Fat, protein and lactose were assessed as milk composition parameters. To evaluate milking cows by effective factors; three different stage of lactation (SL) (SL 1=90d<, SL 2=91-150d and SL 3=151 <= d), five parity, four calving season (CS) and three body condition score (BCS) groups (group1=<3 points; group2=3-3.50 points and group3=>3.50 points) were designed. While fat, protein and lactose decreased, daily milk yield (DMY), 305 daily milk yield (305 DMY) and SCC increased with advanced parity. Fat, protein and SCC increased, but lactose and DMY tended to drop with later SL and BCS. These parameters were highest in cows calved in winter-autumn, summer, winter-spring and winter-autumn, respectively. DMY negatively correlated with investigated parameters except for lactose and 305 DMY. The study revealed that non-genetic factors are associated with milk composition, yield and SCC of milk. Therefore, it is suggested that these factors should primarily be considered to obtain more quality and quantity milk from dairy cows.
