In the milking parlour, feeding with concentrates was analysed in order to establish whether too short time for the consumption of concentrate caused increased heart rate (HR), one of the stress indicators. Average HR was 82.38 min-1. In the evening, milking cows had higher HR (83.4 min-1), compared to the morning one (81.2 min-1). In the second month after calving, HR of cows was higher (85.10 min-1) compared to the first (81.04 min-1) and the third month (80.79 min-1) after calving. Higher quantity of consumed concentrate (over 3 kg) resulted in an increased HR. If the cows received larger quantities of concentrate, HR increased towards the end of milking process. It can be concluded that large quantities of concentrate, which could not be consumed in a short period of available time during milking, caused stress in highly productive dairy cows.

Key words: heart rate, dairy cows, milking parlour, Polar monitors,

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