Abstract
In standing dairy cows, the medial claws carry most of the load of the forelimb. The goal of our experimental study was to investigate how even load distribution can be achieved between the paired forelimb claws through foot trimming. We measured vertical ground reaction forces, mean and maximum pressures, and contact areas under the sound forelimb claws of 28 nonlame dairy cows using a force plate and a pressure plate. The experimental setup consisted of 3 measurement situations: (1) baseline measurements made after routine foot trimming, (2) measurements made with plywood plates, 3 mm in thickness, attached to both lateral claws, and (3) measurements made with the same plywood plates attached to both medial claws. After routine foot trimming, the medial claws carried 70.1% of the entire forelimb load with its palmar zone bearing 54.0% of the entire forelimb load. Even load distribution between the paired claws was achieved when the plywood plates were attached to the lateral claws, whereas plates on the medial claws increased the load discrepancy. The pressures on the medial claws were reduced by attaching the plywood plates to the lateral claws but remained uneven between paired claws and claw zones. The palmar zone of the medial claws was the region subjected to the greatest force and highest pressures in all situations. A drawback of the study was that the plywood plates increased the contact area and therefore reduced the mean and maximum pressures in the claws they were attached to. We concluded that equal load distribution between the forelimb claws was achieved in our setting when the lateral claws were left 3 mm higher than the medial claws.
Lüchinger, Isabelle