Assessment of dairy cow locomotion in a commercial farm setting: The effects of walking speed on ground reaction forces and temporal and linear stride characteristics

Objectives of this study were to determine the effects of walking speed on ground reaction force (GRF) parameters and to explore inter- and intra-individual variability with unsupervised data collection in a commercial farm setting.We used eight high producing loose-housed Holstein Friesian cows consistently scored sound, with no veterinary treatment during the collection period. Cows walked freely (0.52-1.37 m/s) over a five force platform array, twice daily, following milking. GRF data were split into speed categories and temporal and kinetic gait parameters extracted. A general linear model was carried out to determine effects of speed.Variation in parameters between cows is inconsistent, while between speed categories (containing data from multiple cows) the parameters which vary are consistent. Stance and stride time were reduced with increasing speed but no change in peak vertical GRF or duty factor was found. This ability to track parameters within an individual over time aids detection of subtle changes associated with lameness.