BACK TO QUEBEC CITY 2002 TITLES
Cow traffic in automated
milking systems
J. Rushen1, L. Munksgaard2,
A.M. DePassillé1 and C.C. Krohn2
1Agriculture and Agri-Food
Canada, Lennoxville, QC, Canada; 2Danish Institute of Agricultural Sciences,
Foulum, Denmark
With automatic milking, cows with free access to feeders (free-traffic) may not be milked often enough. To increase the frequency of visits to the robot, farmers may force cows to enter the robot to reach the feeders (forced-traffic). However, this may reduce feeding time. To compare free and forced traffic, and to identify behavioural characteristics of cows that visit the robot infrequently, we examined two groups of 35 cows, each having access to one robot. For 21d, one group had free access to feeders, while the other group had forced traffic. For a subsequent 21d period, the treatments were switched. Cows were scan sampled for 2X24 h periods noting the number eating, in feed area, in stalls, or waiting. Milking data were obtained from the robots. All cows were milked 2-4 times/d, with no difference between free and forced traffic. Daily milk yield correlated with the number of milkings (r = .33; P <.05 ). The robot was used continuously throughout the day, with little diurnal variation, but with many visits without milking. Cows lay down for 12 h/d with no difference between free and forced traffic. There was marked diurnal variation in feeding. Total duration of feeding did not differ between free and forced traffic, although forced traffic reduced the frequency of visits to the feeders (P <.05). There was a positive correlation between the number of visits with milkings and the number of visits without milkings (r = .56; P <.05 ). In both types of traffic, there was a negative correlation between the number of visits to the robots and the time spent in the stall area (r = -.44; P <.05 ). Voluntary attendance with free traffic was high and use of forced traffic did not improve access to the robot or reduce feeding time but reduced the frequency of feeding visits. Individual differences in cows’ use of the robot may reflect the way cows balance their time between feeding and resting but marked diurnal variation in resting and feeding can occur without causing marked diurnal variation in visits to the robot.