This experiment investigated the effects of providing access to grass silage on the welfare of sows
introduced to a large dynamic group. Two treatments were applied: (1) access to racks containing grass
silage (offering an average of 1.9 kg silage/sow/day), and (2) control treatment with no grass silage racks. It was found that overall the levels of aggression to which newly-introduced sows were exposed on the day
of introduction to the group were low, and did not differ significantly between treatments. In
addition, injury levels measured 1-week post-introduction to the group did not differ significantly between
treatments. Sham chewing behaviour was more prevalent in the post- rather than the pre-feeding
yard, and was significantly reduced in both resident and newly-introduced sows when silage was
provided