Lameness was also visually scored on a weekly basis using a four point assessment scale; where 0 = normal and 3 = severely lame. Sows were classified as non-lame (score ≤ 1) or lame (score ≥ 2). Based on the visual weekly assessments and the force plate readings, a lameness detection decision tree was created. This decision tree was consistent with visual assessments 95.98% of the time. Comparing the two lameness detection techniques, the force plate identified lameness on average 4.62 days sooner than the visual assessment. Through the trial, the force plate only required minor maintenance including calibration of quadrants and tightening of screws. One quadrants plate needed to be replaced as the non-slip surface on it had started to wear off. Results suggest that the force plate can detect lameness in a commercial setting earlier than weekly visual assessments while requiring minimal maintenance.
Key Findings:
• The force plate can be successfully installed in a commercial setting under an ESF with some mechanical maintenance and modifications including routinely calibrating the load cells to be sure measurements are accurate.
• A decision tree created based on the information gathered from the force plate can accurately detect lameness earlier than a weekly visual assessment.
• If producers using an ESF system can detect lameness earlier, then management practices for lame sows could be modified to trigger the gait on the ESF to send sows classified as lame into an isle or alternative pen where the stockman would easily identify them and provide a course of action for each sow.
• Further modifications are required to allow the force plate as currently designed to be commercially viable to collect data form a wide range of pigs (from gilts to mature boars).
• Future prototypes could include shorter front plates and a taller center bar to correct these problems.