Gait and force analysis of provoked pig gait on clean and fouled rubber mat surfaces

Materials that increase floor friction forces in absorption of foot pressure could reduce the risk of slipping, i.e. promote walking safety. The effects of fouled rubber mat floor condition on the gait of 10 pigs walking in a curve, using kinematics and kinetics to record gait parameters and slip frequency, are described and compared with clean conditions. Pigs adapted to fouled floor conditions through reduced walking speed (10%), prolonged swing and stance time, and a higher number of 3-limb support phases, but kept stride length and diagonality constant. This adaption produced a threefold reduction in lateral horizontal forces and kept braking and propulsion forces constant, resulting in a constant peak utilised coefficient of friction (UCOF) level in fore limbs but a 31% reduction in UCOF in hind limbs. The better traction for pigs walking on rubber matting compared with concrete is due to a more effective transmission of forces from the limb to the elastomer, dissipating the forces into energy within the material, and thus impeding the effect of centripetal force, with less displacement of body centre of gravity and less forward and backward slip. Pig forward slip frequency on fouled rubber matting was 65 and 51% lower for fore and hind limbs respectively compared with pigs walking a curve on fouled concrete. The soft flooring material improved gait adaption and could thus improve walking safety.