Genetic uniformity in livestock breeds optimized for yield creates welfare vulnerabilities. Preserving heritage breed diversity maintains resilience, behavioral complexity, and adaptive capacity in farm animals.
The welfare costs of extreme genetic selection in commercial livestock are substantial and well-documented: fast-growing broilers develop myopathy and leg problems, high-yield dairy cows experience metabolic disease and early culling, and highly prolific sows suffer reproductive strain. Heritage breeds, selected over centuries for adaptation to local conditions, typically show more moderate growth and production rates that do not push physiological limits in the same ways. They also maintain behavioral repertoires that commercial selection has partly eroded. Preserving genetic diversity is simultaneously a welfare and resilience intervention: diverse gene pools provide the raw material for breeding programs that can respond to emerging disease threats and climate change impacts that uniform populations cannot.