Effect of flooring system on locomotion comfort in dairy cows

The aim of the thesis was to study influence of different flooring systems on several aspects of locomotion of dairy cows. To assess the gait on different floors, trackway analysis was used. Cows walking on a hard, slippery surface had shorter strides, wider posture and asymmetric steps. A hard, slippery surface resulted in stride shortening, wider posture and asymmetric gait. Using soft rubber mats made gait patterns more similar to those on a natural yielding surface such as sand. When cows with moderate lameness walked on yielding surfaces their gait parameters associated with lameness were less pronounced than on hard concrete surfaces. Preference studies showed that the majority of cows preferred to walk and stand on soft rubber flooring rather than on concrete flooring. However, lame cows within the group did not show a stronger preference to walk on soft flooring than non-lame cows, presumably due to lower social rank compared to healthy herd mates. In order to assess the effects of long-term exposure to flooring systems differing in hardness and abrasiveness installed in the walking and standing areas an experimental study was carried out. Claw conformation, claw horn growth and wear rates, as well as static weight and pressure distribution were evaluated. On a rougher flooring (mastic asphalt), exaggerated wear, highest growth rate and a loss of sole concavity was seen, and most weight was exerted to the sole area of the claws. When rubber-equipped feed-stalls were used together with mastic asphalt in alleys cows showed reduced wear, positive net growth and reduced loss of the concavity compared to cows housed on asphalt alley surfaces. In comparison with asphalt flooring, rubber mats on the alleys resulted in lower growth and wear rates, increased net growth, preserved sole concavity and the bulb and wall area of the claw carried the most weight. Rubber mats together with little exposure to an abrasive asphalt surface resulted in claw horn net growth rates similar to that observed on aged, low abrasive concrete slatted floor. It was concluded that soft flooring provides good locomotion comfort for dairy cows but a moderate abrasion is also required to prevent claw overgrowth