Effect of Slat and Gap Width of Slatted Concrete Flooring on Sow Gait Using Kinematics Analysis

Simple Summary The housing of gestating sows is currently moving from individual stalls to group housing in most Western countries. If the design of slatted concrete floors was well studied for smaller animals such as finishing pigs, less information is available for sows. Slatted concrete floors can have negative effects on sow health, especially in connection with lameness. The aim of this study was to determine the optimal slat and gap widths of slatted concrete floors for the ease of movement of sows. After testing several combinations of slat and gap widths and quantifying the gait of walking sows using kinematics analysis, we determined that the usual 25-mm gap/125-mm slat commonly used in North America may not be optimal to facilitate the ease of movement of sows. In particular, sows' gait was less affected by smaller gap widths. Further research is now necessary to assess the impact of floor design on behavior, lameness occurrence, performances and longevity of sows. Abstract The housing of gestating sows in groups requires sound information about the adapted design of the pen floor. Slatted concrete floors are commonly used for effective drainage of manure but can cause feet injuries and lameness. In the present study, kinematics were used to characterize the gait of 12 gilts and 12 lame sows walking in a corridor on slatted concrete floors with different combinations of slat (85, 105 or 125 mm) and gap (19, 22 or 25 mm) widths. The nine experimental floors were tested with slats in the perpendicular and parallel orientation to the direction of animal walk, according to a duplicated lattice design. Gait parameters were quantified using spatial, temporal and angular kinematics for front and rear limbs. Some parameters were significantly affected by the treatments (p < 0.05), but the effects differed between gilts and lame sows and between slat orientations. Gap width had a significant effect on parameters such as back angle, stride length, foot height, and carpal and tarsal joint angle amplitudes. Slat width significantly affected parameters such as foot height, and carpal and tarsal joint angle amplitudes. Comparisons of the different combinations of slat and gap widths revealed that slats with a width of 105-125 mm and gap width of 19-22 mm had the least effect on the gait characteristics of the gilts and sows.