Farrowing crates confine sows during and after birth to prevent piglet crushing, but cause significant maternal welfare costs; alternative systems that prevent crushing without full confinement are in development and use.
The farrowing crate welfare dilemma is genuine: sow welfare suffers in crates, piglet mortality rises in some loose systems. The research consensus is that well-designed loose farrowing systems with appropriate pen structure, bedding, and management can achieve sow welfare without unacceptable increases in piglet mortality. The key design features — adequate space, nest-building material, low-escape barriers, and experienced stockpersonship — are known. The remaining barrier is the cost of retrofitting existing buildings and the management skill required for loose systems.