Rooting is a fundamental behavioral need for pigs, and providing appropriate substrates — particularly straw and soil — allows expression of this highly motivated behavior with significant welfare benefits.
Depriving pigs of rooting substrate is one of the most clear-cut welfare failures in conventional intensive pig production. Pigs housed without manipulable material are unable to perform a highly motivated behavior that represents a central component of their behavioral repertoire. The resulting frustration drives oral manipulation of pen mates, leading to tail biting and ear damage that cause further welfare problems. Providing straw is one of the most cost-effective welfare improvements available in pig production, yet economic and practical pressures in many systems continue to prevent its adoption.