Krohn, C. C., Munksgaard, L., Jonasen, B. 1992. Behaviour of dairy cows kept in extensive (loose housing/pasture) or intensive (tie stall) environments. I. Experimental procedure, facilities, time budgets - diurnal and seasonal conditions. Applied Animal Behaviour Science 34, 37-47.
Twelve dairy cows were placed in a stimuli-rich environment, a 'dairy cow park', for 2.5 years. .. During summer the cows spent 17.2 h outdoors each day, mostly at pasture. .. During summer, the cows walked 2.5 km daily and spent most of the nights at pasture.
Year
1992