Influence of floor type on the locomotion of dairy cows

Locomotion in 36 cows was tested on five different surfaces: solid and slatted concrete with and without 20 mm thick elastic (KEN 1 ) rubber mats and wet, compressed sand (as an example of a natural, yielding surface). The friction of the floors was measured and a trackway measurement system (measurements from footprints) was used for analysis of locomotion. The presence and severity of lameness was scored subjectively. The slatted, crude concrete floor was found to have the lowest coefficient of friction (0.31), the solid, crude concrete floor had a higher friction coefficient (0.58) and rubber mats had an intermediate friction value (0.46). In comparison with the sand surface the cows walked more slowly on the slatted, crude concrete floor, with considerably shortened strides and with the rear feet placed at greater distance behind the front ones. On the solid, crude concrete floor the cows took shorter strides and steps than on the sand surface, but the speed did not differ significantly. Elastic rubber mats on the solid as well as on the slatted concrete floor increased the length of strides and steps. In comparison with non-lame and mildly lame cows, moderately lame animals walked more slowly and had a shorter stride and step length. Analyses within each lameness degree revealed that the moderately lame cows walked with a significantly smaller step angle (which corresponds to a wider posture) on crude solid and slatted concrete in comparison with both the continuous and the slatted rubber floor. The moderately lame cows walked on the rubber mats with roughly the same step angle as on the sand surface. Comparisons of cows with different