Photogrammetric analysis of limb joint angles in cows with normal gait before and after hoof trimming.

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. The aim of this study was to evaluate the effect of hoof trimming on overall limb movements by comparing the changes in 8 limb joint angles 1 wk before and 1 wk after hoof trimming. Seventeen Holstein-Friesian dairy cows that were able to move freely and had no history of hoof diseases were included in the study. The cows were walked on rubber mats with a high friction coefficient (HFM) and a low friction coefficient (LFM) due to the spraying of sodium polyacrylate. Each cow had 15 reflective markers applied to its right side. A high-speed camera was set to 200 frames per second (fps) on the image analysis software, and the images of the cows were captured while cows walked on the test mat. The tests were conducted 1 wk before and 1 wk after hoof trimming, and the cows were trimmed by the functional hoof trimming method. With image analysis software, video clips of walking cows were confirmed visually and tracked during 1 gait cycle by each reflective marker attached to the hoof of the forelimb and hindlimb, after which the stance phase and swing phase were identified. The durations of the stance phase and swing phase of the forelimb and hindlimb, respectively, and the maximum, minimum, and range of motion (ROM) values of the 8 joint angles (shoulder joint, elbow joint, carpus joint, forelimb fetlock joint, hip joint, stifle joint, hock joint, and hindlimb fetlock joint) during 1 gait cycle were included in the analysis. The maximum and minimum angles of the hip and stifle joints were narrower after hoof trimming than before, although the ROM did not change and was clearer for HFM than for LFM. It was thought that the flexion of the proximal hindlimb would progress smoothly during walking after trimming. [ABSTRACT FROM AUTHOR]