Two case studies on farms combining automatic milking with grazing - time budgets, synchronization of behaviour and visits to the machine.

Abstract

We investigated the behaviour of the cows and visits to the robot at two private farms, which differed considerable in their management routines. At both farms there was one robot and approximately 65 Danish Friesian cows, which had access to pasture during the day. Herd 1 had free traffic and cows were only fetched from the pasture once a day; Herd 2 had forced traffic and cows were fetched from pasture more times a day. Each farm was visited three times in the grazing season. Occurrence and synchronization of “standing/walking”, “lying” and “eating” was observed at pasture and in the barn in the fall. Furthermore cow traffic in and out of the barn was observed. In herd 1 most cows left the barn immediately and in 79% of the observations 75% or more of the cows were at pasture. In herd 2 it took around three hours before most of the cows had left the barn, and only in 31% of the observations 75% or more cows were at pasture. The behaviour of the cows were more synchronised when being at pasture than in the barn (P<0.001). On both farms the cows almost always left/returned to the barn in groups, only in 4% (Herd 1) and 7% (Herd 2) a cow was leaving/returning to the barn with an interval of more than 9 minutes to the cow leaving/arriving before of after. Milking frequency were 2.5 times (herd 1) and 2.7 times per day (herd 2). When the cows had access to pasture the number of milkings per hour decreased in herd 1 compared to the remaining part of the day (2.6 versus 8.0), but not in herd 2 (7.0 versus 7.3). In conclusion, the behaviour of the cows were more synchronised at pasture and cows rarely went to the barn alone. Differences in management routines had a severe effect of the use of the robot.