The change in pressure distribution when an animal with claw problems tries to move leads to specific lesions at the claw sole, which tends to reach the soft tissue causing pain and lack of welfare. Older animals (finishing pigs and sows) are particularly subject to locomotion problems caused by claw injuries, as the use of fogging to reduce heat stress and close contact with urine and manure residues on the floor can reduce claw hardness. The objectives of this research were to simulate in laboratory, the static claw pressure distributions of pigs standing on a hard surface compared to rubber flooring; and to measure the dynamic effects in the field, using live animals with normal gait using a piezoelectric sensing device and to correlate the regions of the claw under most stress to the defects frequently found in commercial pig production. It was found that the rear outer claws are severely overloaded when compared to rear inner claws and front
claws (irrespective of digits) and that is associated with the reported pathologies found in the literature (cracks and sole
ulcers). Also, that applying cushioning through the use of rubber mattresses may reduce the overloading of claws, mostly the rear outer claws, and this may prevent defects from occurring.

For more information the full article can be found at  http://www.sciencedirect.com/science/journal/15375110