Nesting behaviour is one of the most strongly motivated behaviours in sows before birth, and providing materials for this fundamental need is essential for welfare.
Nesting behaviour deprivation is one of the clearest examples of welfare compromise caused by intensive farming. Sows prevented from performing this highly motivated behaviour show repetitive vacuum nesting movements, elevated cortisol and impaired maternal behaviour after birth. The evidence is so clear that EU law requires provision of nesting materials before farrowing. However, implementation is inconsistent and material quality varies widely. Providing adequate nesting materials directly reduces suffering during one of the most physiologically and psychologically demanding periods in a sow's life.