Do Rubber Floor Mats Prevent Lameness in Gestating Sows Housed in Large Groups? A Field Experiment on Three Commercial Farms in France

Simple Summary: In the European Union, gestating sows are housed in groups in pens that often have slatted floors. Slatted floor can cause injuries to the animals' legs and hooves, leading to potentially painful lameness. The purpose of our study was to verify if the installation of rubber mats on their floors could limit the occurrence of injuries and lameness in gestating sows. Mats were installed on three commercial farms for use over two consecutive sow pregnancies. The mats limited the occurrence of inflammations around the sows' leg joints but had no impact on the occurrence of lameness or leg and hoof injuries. The benefit of mats would be greater if they were available throughout the sows' lives and not just during the gestation period. However, the mat design tested was unsatisfactory because manure did not drain well off the mat and sows were dirtied quickly. Lameness and foot disorders are major health and welfare issues in intensive swine production systems. They are exacerbated when sows are housed in large groups on slatted concrete floors during gestation. Our study aimed to assess the effect of rubber mats in the lying area of the gestation pen on lameness and leg health in gestating sows housed in large pens in commercial conditions. The study was conducted on three commercial farms over two successive gestations. A total of 582 Large White x Landrace sows, housed in 10 static groups, were enrolled: 5 groups in pens with rubber mats and 5 groups on slatted concrete floors. Lameness, bursitis, leg injuries, claw growth defects and claw lesions were measured at the beginning, middle and end of each gestation period. The rubber mats decreased the risk of suffering from bursitis, but had no effect on the risk of lameness, leg injuries, claw growth defects or claw lesions. Sows housed on rubber mats were heavily soiled compared with those on slatted concrete floors because the mats were not perforated for slurry evacuation. Locomotion disorders and foot lesions remained prevalent despite the rubber mats in the lying area of the gestation pens, but adding rubber mats in service rooms and farrowing crates may produce better results.