Effects of early social mixing and genetic line on female piglet activity, pen location and social interactions pre- and post-weaning under Swedish commercial pig production conditions

This study investigated activity, preferred pen location and social interactions in female piglets (0-10 weeks of age, N = 98) intended for breeding. Piglets were housed in pens where the sow and the piglets were loose-housed without (CP) or with access to the neighbouring pen week 2-5 (AP). Female piglets of two genetic lines (Dutch and Swedish Yorkshire (DY, SY)) from 26 litters were selected within 24 h after birth. DY piglets in the AP treatment spent more time in the neighbouring pen than SY (24.0% vs 19.0%), while AP piglets of both genetic lines spent less time lying down before weaning than CP. At weaning, CP piglets increased their time in the piglet corner and spent less time lying. SY piglets were less responsive to social interactions. The results confirm previous findings on favourable effects of early social mixing on piglets' behavioural responses to weaning also when sows are individually loose-housed.