Behaviour of 3-week weaned pigs in Straw-Flow(R), deep straw and flatdeck housing systems.

The behaviour of 3-week weaned pigs in different housing systems was examined as part of an assessment of the suitability of the Straw-Flow(R) system for pigs of this age. Three replicate pens of 20 pigs were weaned at 6.4 kg liveweight into each of: (a) deep-straw; (b) Straw-Flow(R); (c) large flatdeck; (d) small flatdeck. A kenneled lying area was provided in (a) and (b). The floor in (c) and (d) was expanded metal. Stocking densities were 0.23 m(2)/pig in (a), (b) and (c), and 0.17 m(2)/pig in (d). After 4-5 weeks (at 19.6 kg liveweight), 16 pigs from each pen were moved into Straw-Flow(R) grower pens (0.68 m(2)/pig) and observed until slaughter at 90.6 kg. Pigs in systems incorporating straw showed behaviour patterns associated with increased welfare (greater straw-directed behaviour and less pig-directed and pen-directed behaviour) relative to those in barren pens. Behavioural differences between (a) and (b) related to differences in available straw; there were few differences between (c) and (d). Pigs from (c) and (d) showed increased rooting relative to those from (a) after transfer to the grower pens, but other behavioural differences between weaner treatments did not persist. It is concluded that the Straw-Flow(R) system can provide suitable accommodation for weaned pigs.