Pig Weaning Stress: Causes and Welfare Solutions

How early weaning in commercial pig production causes significant stress for piglets and sows, and what welfare-friendly alternatives look like.

Key Facts

Commercial pigs are typically weaned at 21-28 days, far earlier than the natural weaning age of 3-4 months
Post-weaning stress syndrome combines social, nutritional, and psychological disruption in one event
Cortisol levels in piglets spike dramatically at weaning and remain elevated for several days
Piglets weaned at older ages show less stress, better immunity, and fewer post-weaning health problems
Natural suckling behaviour continues until 13-17 weeks in studies of semi-feral pigs

Welfare Considerations

Commercial pig weaning is one of the most concentrated welfare events in livestock production. At weaning, piglets simultaneously lose their mother, their familiar social group, their primary food source, and their environment — all at an age when they are still physiologically immature. The result is a well-documented welfare crisis: post-weaning diarrhoea, aggression, failure to thrive, and immune suppression are all consequences of weaning stress. Extending the weaning age even by a week or two significantly reduces these outcomes, but this requires management changes that have production and economic implications. The welfare case for later weaning is strong, and the question is how to make it economically viable.

What You Can Do

Choose pork from farming systems that specify later weaning ages or family penning systems
Advocate for minimum weaning age requirements to be incorporated in farm animal welfare legislation
Support research into cost-effective systems that allow later weaning in commercial pig production
Engage with certification schemes to ensure weaning standards are included in welfare audits
Learn about the full welfare cycle of pigs from birth to slaughter when making purchasing decisions