Gestation sow housing exists on a spectrum: individual gestation stalls (smallest space, most restrictive), small groups (4-10 sows), large groups (50-300+ sows), and outdoor systems. Each system has different welfare profiles. Individual stalls severely restrict movement and social behavior; large groups risk competitive injury; outdoor systems expose sows to environmental extremes.
Group-housed gestating sows show significantly better welfare on behavioral measures: higher activity levels, more social interaction, better body condition maintenance, and lower stereotypy rates than stall-housed sows. Electronic Sow Feeding (ESF) allows individual feeding in group settings, reducing resource competition. Aggression at ESF stations requires careful management.
Farrowing crates restrict sow movement to protect piglets from crushing. Individual farrowing crates allow sow to stand and lie but not turn. Free farrowing pens allow full movement and natural nesting behavior. Research shows sows in farrowing crates show higher stress and frustrated nesting behavior; free farrowing sows show natural pre-farrowing behavior but may have slightly higher piglet crushing rates in poor design.
Well-designed free farrowing systems (PigSAFE pen, Solari pen, comfort pen) reduce piglet crushing risk through spatial design: separate 'escape' areas for piglets, sloped floors that encourage sow positioning, and nest areas that reduce piglet exposure. Countries including Norway and Sweden have largely phased out farrowing crates. Denmark is transitioning.
Suckling 10-14 piglets for 3-4 weeks places extreme physiological demands on sows. Lactation body condition loss is a welfare and reproductive concern. Ad libitum feeding and water access during lactation support welfare and productivity. Creep feeding from day 7 reduces competition on sow teats.
Welfare-positive sow housing systems have higher capital costs but often improved productivity outcomes. Group gestation housing reduces cardiovascular disease and lameness in sows (improving productive life). Free farrowing reduces sow stereotypies correlated with stress-induced reproductive failure. Long-term economic analysis increasingly supports welfare investment in sow housing.