Enrichment Material Consumption in Pigs

The European Council requires that pigs must have permanent access to manipulable material [Art. 3 (5 (link)), Annex 1 (4 (link))]. To comply with the legislation, two types of enrichment material were provided; either a rubber floor toy (weaner stage) or plank of wood (finisher stage) and a rack of fresh grass (Perennial Ryegrass and White Clover swards, both stages). Prior to the start of the experiment and at the end of each stage, the rubber floor toy and plank of wood were weighed to determine consumption by the pigs.
Metal racks (0.59 × 0.26 × 0.25 m) were fitted on the front wall of each pen adjacent to the corridor (0.6 m above ground and 0.8 m from the feeder). Racks were 27 cm in length in both the weaner and finisher stages (Figure 2). The grass was added two times a day to ensure that pigs had ad libitum access. The weight of the grass was recorded whenever it was renewed, and the total sum for each pen during each stage (weaner and finisher) was calculated.