Table 2.
Environmental enrichment materials and objects according to the categories included in the Commission Recommendation (EU) 2016/336, and their main effects on fattening pig behavior.
| Animal | Enrichment | Duration of Behavior Observation | Main Effect | References |
|---|---|---|---|---|
| fattening pigs | straw bedding * compared to slatted floor pens with different number of hanging toys *** | 6 h daily in the week of entry, the week before the group size reduction and a week before slaughter | decrease of pen mate manipulation and increase of investigation of straw bedding | Scott et al. [68] |
| fattening pigs | straw rack**, metal chain***, wood shavings**, and additional pieces of fresh birch wood**, polythene pipes***, or two crosses of metal chain***; combination pens had all of the enrichment materials mentioned above | after 2.5 months of exposure to the objects, one day of video observation was performed | increased object exploration best seen in pens with fresh wood, as well as reduce of tail and ear biting | Telkänranta et al. [70] |
| fattening pigs | piece of hard wood attached to chain ** | 3 h daily, nine times over 16 weeks | decrease of aggression and tail biting | Cornale et al. [28] |
| fattening pigs | chain *** and compressed straw block in dispenser * | 2.5 h daily, once a week through the entire finishing stage | decrease of pen mate manipulation | Bulens et al. [93] |
| fattening pigs | PCV pipes with four pieces of plastic tubing attached to it *** | 8 h daily, for six consecutive days | increase of activity | Machado et al. [95] |
* optimal, ** suboptimal, *** marginal materials according to the categories included in the Commission Recommendation (EU) 2016/336 on the application of the Council Directive 2008/120/EC, laying down the minimum standards for the protection of pigs with regards to measures to reduce the need for tail-docking [9].