Inger-Lise Andersen

Behaviour of sows and their piglets in different crated and free farrowing systems

Piglet mortality due to maternal overlying and piglet starvation caused by sibling competition increases with larger litters, especially in loose-housing systems. Nest-building, sow-initiated communication with the piglets and maternal carefulness, are all vital traits for piglet survival that are underemphasized in crated systems. While semi-crated systems offer more freedom than crates, sow welfare is still highly compromised, and a natural interaction with piglets remain limited. An optimal farrowing pen must provide sufficient space for sows to turn around and orient while communicating with their piglets. Clear separation between nest/rest and activity/dunging areas is crucial. Key features for improving piglet survival include access to nest-building materials, enough space for sows to turn and nurse, and sloped, solid walls to reduce crushing risks. Floor heating in the nest area can help newborn piglets dry faster, retain heat, and nurse sooner. Many farrowing pens assume piglets will leave the sow for a warm creep area. However, under natural conditions, piglets stay close to their mother for warmth, protection, and access to milk. Even in high-quality creep areas, piglets prefer resting in body contact with their mother during the first two days. Staying close to the sow provides piglets with the best chance of survival through warmth, comfort, and access to a teat during the colostrum period. For individually loose housed or group housed sows, systematic management routines around the time of farrowing are needed to achieve the same level of piglet survival as in crated systems.