Behaviour of cattle using an automated feeding system

Cattle behaviour using automatic out-of-parlour concentrate dispensers was studied as part of research investigating the effects on health of feeding concentrates in small quantities throughout the day. Three groups of 20 heifers, each at a similar stage of pregnancy, were observed throughout 24 h at 2 weeks before calving and on 5 further occasions at 4, 10, 16, 22 and 28 weeks after calving. In the system, each animal is allocated a daily ration of concentrates, which in this experiment was between 2 and 8 kg/day, determined mainly by milk yield. The quantity of this ration available each time the animal visits the dispenser is proportional to the time which has elapsed since the animal's previous visit. Each animal paid fewer visits to the dispenser (14/day) during the first period of observation after calving than during the other periods (mean 22/day). The heifers were less active between 22.00-06.00 h (night) than between 06.00-22.00 h (day), spending less of the night either standing (19 v. 40 mins/h) or feeding from a trough of silage fed ad libitum (3 v. 15 min.h). However, the dispensers were used approximately equally during the night and day (16 v. 18 min/h). In a second experiment, conducted during the summer grazing period, a herd of 60 cows was observed using the dispensers for 3 periods of 24 h. In order to visit the dispensers, the cows had to walk back from a grazing area and into a building. Animals in the early stages of lactation (0-90 days post-calving) visited the dispensers more frequently than animals at later stages of lactation (18 v. 10 times/day) and spent more time in the building (6 v 2 h/day). As in the experiment with heifers, the dispensers were used approximately equally during the night and day (17 v. 20 min/h).