Farrowing is the process of pig birth and early lactation. Sows (female pigs) naturally build nests before birth, are highly motivated to root and arrange bedding material, and require private space for the birth process. After birth, they nurse piglets (typically 10–14 per litter) for 3–4 weeks. The welfare challenges of farrowing in intensive production relate to both the confinement of the sow and the risk of crushing (overlay) of piglets.
Standard farrowing crates measure approximately 60 cm × 200 cm — barely larger than the sow's body. For 4–6 weeks (pre-farrowing preparation plus lactation), sows cannot turn around, perform nest-building behavior, or move freely. Research consistently shows:
Piglet crushing (overlay) is a leading cause of pre-weaning piglet mortality, accounting for 30–50% of deaths before weaning in loose-housed systems compared to 10–15% in crated systems. Piglets crushed by sows die of asphyxiation — a welfare-significant death. The farrowing crate protects piglets by preventing sow movement during the highest-risk period. This piglet welfare argument is the primary defense of farrowing crate use by industry.
Free farrowing pens allow sow freedom of movement throughout farrowing and lactation while providing physical design features to reduce crushing: sloped floors forcing sows to lie against walls (away from piglets), heated creep areas attracting piglets to safety zones, and dividers protecting piglets during sow posture changes. Research from Scandinavian countries and the UK shows that well-designed free farrowing pens can achieve piglet mortality rates approaching conventional crate performance (12–18% pre-weaning mortality vs. 10–15% in crates).
Systems that confine sows only around the time of birth (72–96 hours) and then open the crate for the remainder of lactation represent a compromise. Sow welfare is significantly improved compared to full crating — movement, social interaction, and natural behavior are possible during most of lactation. Piglet welfare during the post-confinement period approaches free farrowing performance. These systems are now commercially available from multiple European equipment manufacturers.
Sweden banned farrowing crates in 1988 — the longest-running large-scale evidence base for crate-free farrowing. Swedish free farrowing pens with PigSAFE-type design achieve commercial viability with manageable piglet mortality. Denmark, which has one of the world's most productive pig industries, is transitioning away from crates with a legislative phase-out timeline that includes requirements for freedom farrowing in all new builds from 2035.
Key farrowing crate legislation in 2025:
The transition to free farrowing requires capital investment in new pen systems (£1,500–4,000 per pen vs. £500–800 per crate), potential increased piglet mortality in poorly managed transition periods, and enhanced stockperson skill in monitoring piglet welfare. However, research shows that motivated, trained stockpeople achieve excellent piglet welfare outcomes in free farrowing systems, and that the capital cost amortizes over the operational life of facilities.
Retailer engagement: Marks & Spencer (UK) required crate-free pork from British suppliers as of 2022. McDonald's UK committed to crate-free supply by 2025. These retailer commitments are driving adoption in the UK ahead of legislation.
The transition away from farrowing crates involves honest acknowledgment that some piglet welfare cost is likely in the short term as farm management adapts. Welfare researchers advocate for viewing this through a net welfare lens: the chronic welfare harm of sow confinement for 4–6 weeks per litter, over a productive life of 5–7 litters, represents a significant cumulative welfare deficit. Even if piglet mortality increases modestly in transition, the sow welfare gain may represent a net welfare improvement across the herd.
Tags: Pigs Farrowing Sows Welfare Reform Free Farrowing 2025