The farrowing and lactation period is among the most welfare-significant phases of a sow's life, with implications for both sow and piglet wellbeing.
Farrowing crates cause significant frustration of motivated natural behaviour, particularly nest building. Sows show stereotypic behaviours and increased cortisol during crate confinement. Free farrowing systems using well-designed pens with protective rails can achieve comparable piglet survival to crates while allowing full natural behaviour.