Farm Animals

Pig Nest Building Behaviour Before Farrowing

Nest building is a highly motivated pre-farrowing behaviour in sows, and its frustration in farrowing crates causes significant welfare harm detectable through behavioural indicators.

Key Facts

Wild and outdoor sows build elaborate nests from vegetation in the 24 hours before farrowing
Crated sows show persistent rooting and pawing at the floor in nest-building vacuum behaviour
Providing straw in the pre-farrowing period significantly reduces stereotypic nest-building behaviour
Nest building is linked to maternal behaviour quality and piglet bond formation
Frustration of nest building increases cortisol and may affect colostrum quality and piglet survival

Welfare Considerations

Nest building is one of the most strongly motivated behaviours in the pre-farrowing sow. Its frustration by confinement represents a fundamental welfare failure that straw provision can partially address.

What You Can Do

Support farms providing straw to sows before farrowing as a minimum welfare standard
Advocate for mandatory nesting material provision in farrowing welfare standards
Ask pork producers whether pre-farrowing sows have access to nesting materials