Commercial pig breeding has selected intensively for growth rate and litter size at some cost to health and welfare. Understanding these trade-offs informs welfare advocacy and consumer choices.
Pig selective breeding welfare reflects a tension between production efficiency and animal health that commercial selection has often resolved in favor of efficiency. Litter sizes that exceed maternal milk production capacity require management interventions including split suckling and foster placement, impose metabolic stress on sows, and result in lower birth weight piglets with higher welfare risk. Leg weakness from growth-optimized genetics causes lameness and pain that affects welfare throughout the production period. Genomic selection increasingly allows health and welfare traits to be improved alongside production traits - a convergence that offers hope for breeding programs that achieve both efficiency and welfare goals.