Influence of estrus on changes of locomotion activity and rumination time in cattle dams

The study is focused on the evaluation of the changes in locomotion activity and rumination time in heifers and dairy cows of Holstein breed during estrus. We analysed the locomotion activity and rumination time using the Heatime RuminAct device on 110 dams (78 dairy cows and 32 heifers). We evaluated a total of 298 estrus cycles during the reference period of 3 days before estrus, 3 days after estrus and on the day of the estrus occurrence. The locomotion of cows was expressed in units of locomotion activity in 24 hours (u.24h-1). Rumination time was expressed in minutes in 24 hours (min.24h-1). Based on the results of the study, we established that during estrus, the locomotion activity of dams increases to 888 u 24 h-1 (P <0.001), which represents an increase of +305 u.24 h-1 (+38%). Rumination time of dams was considerably affected by estrus as well and decreased from 582 min.24 h-1 (1 day before estrus) to 482 min.24-1 in estrus time (-43 min.24 h-1).