Voluntary automatic milking in combination with grazing of dairy cows

Automatic milking systems (AMS) enable cows to be milked without human interference. Such systems are more acceptable to consumers and from the animal welfare point of view if they can be combined with grazing in the summer season. In this study, grazing was combined with fully automatic milking for a group of 24 crossbred Holstein–Friesian cows. It was assumed that the cows would visit the AMS voluntarily. Zero grazing (G0) was compared with restricted grazing (cows could spend up to 12 h outdoors daily; G12) and unrestricted grazing (cows could spend up to 24 h daily at pasture; G24). The AMS was continuously available in the cowshed adjacent to the pasture of 1.5 ha. Water was available in the barn, but not at pasture. The average daily milking frequency was 2.3 in G24 compared with 2.5–2.8 in the other treatments (p