The effect of selected factors on milking rate in polish holstein-friesian black-and-white cows

The aim of the study was to investigate the effect of selected physiological factors (age, lactation stage and daily milk yield) on milking rate by Polish Holstein-Friesian Black-and-White cows. The duration of morning, evening and diurnal milking was determined. Milking rate of cows was characterized based on the mean actual and corrected milk yield per 1 minute of milking. Statistical analysis showed a lack of any dependence between the age group of cows and milking duration as well as mean actual and corrected milk yields in the minute of milking. Milking time decreased with progress in lactation. In terms of the mean milk yield the lowest value of this parameter was recorded for cows being in their first stage of lactation (≤ day 40). Cows with greater daily milk yields compared to those producing less milk were characterized by longer milking times and greater mean actual and corrected milk yields in the minute of milking. Milking rate of cows is a functional trait of considerable importance in the economics of raw milk production. The selection towards of an increase in milk yield, may have a positive effect on milking rate in cows.