Researchers in Sweden investigated the long-term effects of different flooring systems on the weight distribution, contact area and contact pressure on the claws of dairy cows housed in a free-stall barn.The four flooring surfaces studied were:
a) low abrasive concrete slatted floor;
b) rubber mats;
c) mastic asphalt floor with feed-stalls;
d) mastic asphalt floor without feed-stalls.
Exposure to the more abrasive flooring (mastic asphalt) resulted in claws having increased contact area at the sole surface and therefore, decreased contact pressure, but the weight bearing role of the the claw wall was reduced. At the same time, because of the abrasive flooring the role of the most important weight-bearing structure, the claw wall, was reduced. The soft flooring, which combines good friction and low abrasiveness, preserved the claw wall, but exposure to the low-abrasive floors transferred weight distribution toward the bulb region. For that reason, short-term exposure to an abrasive surface can be recommended to provide optimal wear and functional claw shape.
source: E. Telezhenko et al., J Dairy Sci 91:1874(2008)