Management of group-housed sows: optimizing mixing time and environmental enrichment to improve welfare and productivity
Pork producers in Canada are in the process of transitioning from stall housing to group housing systems for gestating sows. The greatest concern with this change is the problem of aggression when pregnant sows are mixed. Mixing frequently results in aggressive interactions among sows, and can affect reproduction and cause welfare problems. Typically sows are held in stalls for several weeks after insemination to minimize stress during embryo implantation, however there is increasing pressure to reduce the time that sows are kept in stalls. Earlier mixing times can be used but there is insufficient information regarding these procedures and their consequences for production. In this project, three mixing times will be studied in two different housing systems: i) sows mixed immediately at weaning, ii) sows mixed after insemination, and iii) sows kept in stalls for four weeks and then mixed. Enrichment is also required for sows in groups, and has been shown to reduce aggression. Enrichment devices will be studied to identify suitable enrichment materials for sows. This research will benefit the Prairie Swine Centre by advancing research on the management of group-housed sows. TO BE CONT.