The welfare and productivity of dry sows in different group housing systems in New Zealand. 
This research aimed to evaluate sow welfare and identify potential welfare compromise in specific group housing systems for sows in New Zealand.  The relationship between overall welfare outcome on-farm and sow productivity was also investigated.  Twenty commercial farms were chosen to represent the spectrum of layouts and management practices of New Zealand pork producers.  During a farm visit, housing, management, behavior, welfare, and productivity data were collected.  The following criteria were used to describe each farm: group size, the duration of time in a gestation stall, presence of bedding, feeding method, and feeding frequency.  Sows in medium groups had the most piglets born alive per litter (13.14 piglets).  Sows fed twice daily had significantly higher stereotypies than sows fed at a different frequency.  A welfare index (WI; minimum possible WI = 0.33, maximum possible WI = 5.0) was calculated for each farm and accounted for the following parameters: injuries, lameness, stereotypies, coat condition, and soiling.  The mean WI was 0.65 (± 0.14 SD).  A low WI represented fewer indicators that were associated with compromised welfare.  Thus, existing group housing systems are being managed effectively to achieve good standards of sow welfare.