Pig Crushing and Overlay Mortality Prevention

Crushing of piglets by the sow is one of the leading causes of pre-weaning mortality, and welfare-focused husbandry and housing design can dramatically reduce its incidence.

Key Facts

Pre-weaning piglet mortality averages 10-20% in commercial systems, with crushing accounting for up to 50% of deaths
Farrowing crates were introduced to prevent crushing but severely restrict sow movement and natural behavior
Free farrowing systems with well-designed escape areas can match or better farrowing crate mortality rates
Sow behavior during farrowing and the first 72 hours is the primary determinant of crushing risk
Genetics, nutrition, and stockperson attentiveness all influence crushing mortality in free farrowing systems

Welfare Considerations

The farrowing crate was a welfare solution that created a new welfare problem: preventing piglet crushing by completely immobilizing the sow for weeks. Free farrowing systems demonstrate that with appropriate design - nest boxes, escape creep areas, and attentive stockpeople - piglet survival can be maintained while allowing sows to perform natural maternal behaviors including nest building, turning, and nursing on their side.

What You Can Do

Support pork from free-farrowing certified systems where available
Advocate for phase-out of farrowing crates in favor of welfare-compatible systems
If farming pigs, attend training on free farrowing system management
Support research into free farrowing design that protects piglet welfare
Ask supermarkets and pork producers about their farrowing system policies