Using a Voluntary Walking Test to Evaluate Perforated Rubber-matted and Concrete Flooring Under Different Conditions for Gestating Sows and Gilts

Flooring strongly influences the welfare of gestating animals. Concrete floors are common in the swine industry but may compromise mobility, especially when floors become dirty and wet. Perforated rubber mats may provide a softer, slip-resistant surface with drainage. This study evaluated the locomotion of gestating animals on either perforated rubber-matted or concrete flooring under varying levels of floor soilage. Twenty sows and gilts of varying parities and pregnancy stages were selected and acclimated to handlers, food rewards, rubber-matted/concrete flooring, and a testing runway. Sows were trained to walk voluntarily on an 26ft runway, and each sow was then tested twice on concrete and rubber-matted flooring under clean, dirty, and extra dirty conditions. Walking duration, overall locomotion and individual components of locomotion (caudal sway, stride length, fluidity, and reluctance to bear weight) were measured on a visual analogue scale (0-150mm). Generalized Linear Mixed Models were used on walking duration and different locomotion outcome variables with 2 surfaces, 3 conditions and their interactions as predictors, sow as the random factor and each run for individuals the repeated measure. Overall, animals moved faster on rubber-matted flooring compared to concrete (matted: 22.76±1.67s vs. concrete: 26.05±1.91s; P < 0.001), and this difference was the greatest when the condition was dirty (mat: 19.76±1.57s vs. 25.34±2.03s; P < 0.001). Sows and gilts were scored higher (worse) on overall locomotion scale when walking on the concrete compared to rubber-matted flooring (matted: 20.79±3.42 vs. concrete: 30.65±5.01; P < 0.001), and similarly on caudal sway (P = 0.02), stride length (P < 0.001), fluidity (P < 0.001) and reluctance to bear weight (P < 0.001). Overall locomotion worsened as conditions got dirtier (clean: 12.26±2.05 vs. dirty: 29.34±5.18 vs. extra dirty: 44.70±8.02; P < 0.001), and similarly for stride length (P < 0.001), fluidity (P < 0.001) and reluctance to bear weight (P < 0.001). Perforated rubber-matted flooring shows promising results to improve sows’ locomotion, especially when the condition worsens. A follow-up project is ongoing to evaluate the preference of sows for using different floor surfaces and their long-term impact on sow leg health and productivity.