Genetic selection has shaped modern livestock production profoundly—often prioritizing production traits at the expense of animal welfare. Understanding the welfare implications of past selection decisions, and the growing integration of welfare traits into breeding programs, is essential for sustainable welfare improvement.
Intensive selection for single production traits has created welfare problems that persist today. Broiler chickens selected for rapid growth have bodies their legs cannot adequately support—lameness affects 25-30% of commercial broilers. Dairy cattle selected for extreme milk yield face high metabolic disease susceptibility at peak lactation. Turkeys selected for breast muscle development can no longer mate naturally. In each case, welfare was sacrificed for productivity, creating the welfare deficits that animal welfare science now works to address.
Modern breeding programs increasingly incorporate welfare-relevant traits: Dairy: Longevity, fertility, mastitis resistance, lameness resistance, and temperament are now included in breeding indices. Broiler: Slower-growing breeds selected for leg health and cardiovascular fitness are gaining market share through welfare standards like the Better Chicken Commitment. Pigs: Selection against tail-biting propensity, for calm temperament, and for good maternal behavior is being integrated into breeding programs.
Genomic selection enables rapid improvement of multiple traits simultaneously, including welfare traits that were previously difficult to include due to measurement challenges. Automated welfare phenotyping (camera-based lameness scoring, behavior monitoring) provides the data for genomic selection on welfare outcomes at scale.
Polled cattle (hornless—eliminating dehorning), disease-resistant breeds, and animals selected for positive affective states represent the frontier of welfare-integrated genetic improvement.
Part of the Animal Welfare Hub — 2383+ pages of evidence-based animal welfare information.