Physical comfort for breeding sows — particularly flooring quality and access to nesting material — has a major impact on their health, welfare, and reproductive performance.
Sow physical comfort is a neglected dimension of pig welfare compared to the focus on gestation crates. Even in group housing systems, flooring quality dramatically affects welfare: bare slatted concrete causes abrasions, joint problems, and painful lameness. Sows denied nesting material before farrowing show intense frustration behaviors as they attempt to build nests on bare floors — this is one of the most documented examples of behavioral frustration in farmed animals. Providing even minimal nesting material like straw or shredded paper substantially reduces this frustration and is associated with better farrowing outcomes. Thermal environment also matters: sows are particularly heat-intolerant, and chronic heat stress suppresses reproductive performance and causes ongoing discomfort.