Eating and rumination activity in 10 cows over 10 days.

Eating and rumination activities were evaluated in 10 Brown Swiss cows over 10 days, and the coefficients of variation (CV) were calculated for the investigated variables. A pressure sensor integrated into the noseband of a halter recorded jaw movements during chewing, which allowed the recording of eating and rumination times and the number of regurgitated boluses. The mean CVs ranged from 5.9 to 12.7% and were smaller for rumination (chewing cycles per bolus, 5.9%; daily number of cuds, 8.4%; rumination time, 9.1%) than for eating (eating time, 12.0%; chewing cycles related to eating, 12.7%). We concluded that of eating and rumination variables examined, the number of chewing cycles per regurgitated bolus is the most robust with little variation in individual cows.