Lactating sows in commercial pig production face significant metabolic and behavioral welfare challenges during the nursing period.
Lactating sows in farrowing crates experience significant welfare deprivation during one of the most demanding periods of their lives. Unable to turn around, sows cannot perform the nest-building and rooting behaviors that are strongly motivated around parturition. The inability to respond physically to piglet vocalizations causes behavioral frustration — sows vocalize and attempt to respond but cannot move to attend to their offspring. Extreme body weight loss during lactation indicates metabolic stress. The crate prevents normal bonding behaviors. After weaning, sows are rapidly re-mated to maximize production, preventing recovery from lactation stress. Culling after a few productive years means sows are slaughtered when productivity declines rather than being maintained as valued animals. Free-farrowing systems show that reducing piglet mortality while improving sow welfare is achievable with appropriate housing design.