These systems allow sows and litters to mix before weaning. The majority are based on multi-suckling accommodation and are generally deep-litter systems. They are regarded as being low-cost systems compared to individual pens which require more pen furniture, contributing to additional costs.
There are two traditional, Swedish-based practices for group systems: Ljungstrøm and Thorstensson.
Ljungstrøm-type: For farrowing, sows are initially individually housed in pens (sometimes crates), but are integrated with their litter into groups in larger multi-suckling pens between 10-21 days post-farrowing.
Thorstensson-type: Sows are already grouped prior to farrowing and have free access to individual nest boxes for farrowing, which may or may not be removed 7-10 days post-farrowing.
The below assumes that if Lungstrøm adopted sows are farrowed in loose pens not crates.
The sow is given;
- Freedom of movement at all times
- Opportunity to withdraw into a nest
- Undisturbed nest-site
- Opportunity to nest-build
- Deep straw bed for farrowing
- Separate dunging and nesting areas
- Opportunity to physically contact other sows
- Opportunity to withdraw from piglets
The piglets are given;
- Deep straw bed for thermal and physical comfort
- Opportunity to forage
- Opportunity to mix with litters pre-weaning
Satisfying the staffs’ needs for a safe working environment and ability to manage animal health and welfare will be dependent on whether the sows are individually penned for the initial period. This will allow for greater safety provisions (e.g. lock-out/in mechanism) during the most intensive management period in the early life of the piglets. In addition staff’ needs will be dependent on the management protocols of a particular farm (e.g. non-cross-fostering policy, only vaccinate at weaning etc.).
How to build a Deep Litter Group System
As far as we are aware there are no specific recommendations on dimensions of deep litter group systems. In Thorstensson-type systems, where the sows are grouped from the start, nest-boxes are placed within a much larger area and generally are of simple design measuring 2.00m x 2.00m.