Farm Animals

Pig Genetic Selection Litter Size Welfare

Genetic selection for increased litter size in pigs has created welfare problems through piglet competition, neonatal mortality, and sow metabolic stress that exceed production benefits.

Key Facts

Modern hyperprolific sow lines produce 16-18 piglets per litter exceeding teat number
Surplus piglets cannot obtain colostrum without human intervention
Neonatal mortality in large litters exceeds 20% in many commercial systems
Sow metabolic demands in lactation from large litters cause body condition collapse
Some genetics companies are now selecting for smaller, more viable litter sizes

Welfare Considerations

Selection for extreme litter size has created welfare problems for both sows and piglets that exceed productive gains. Recalibrating selection toward viable litter size improves welfare at scale.

What You Can Do

Support breeding companies selecting for welfare-compatible litter size traits
Advocate for welfare trait inclusion in national pig breeding programme objectives
Raise awareness of extreme litter size as a driver of neonatal mortality
Support research into genetic markers for viable litter size and sow longevity