The introduction of electric fences has allowed a paddock system to be created. There are two main types of paddock layout as follows:
(i) The conventional system is used for most herds and can accommodate large numbers, sometimes up to 1,000 sows. Paddocks are normally rectangular in blocks of four, separated by roadways. They can be laid out to take into account the natural shape and size of fields. Normally paddocks will be allocated for the various parts of the herd including gilts, a training area, service, dry sows and farrowing.
(ii) The radial system is a more recent development more suitable for smaller herds, say from 150 to 300 sows. Wedge shaped paddocks are laid out within a large circle and gated into a small handling and access area at the centre. There is normally a wide track around the perimeter fence and access to the centre which allow servicing of the paddocks. Most operations involving pig movement and handling can be carried out single-handed in this system.