Many popular dog breeds carry heritable health conditions caused by selection for extreme conformation. Breed reform movements are working to shift selection criteria toward health.
Dog breed health reform is one of the clearest examples of welfare harm embedded in the companion animal system. Millions of dogs live with chronic respiratory distress, back pain, heart disease, and neurological suffering because human aesthetic preferences selected for traits that compromise health. The bulldog cannot exercise normally because its compromised airway causes respiratory distress; the dachshund lives with disc disease risk so high that most will require surgery or suffer paralysis; the Cavalier King Charles Spaniel develops heart disease almost universally. These are not inevitable natural conditions but the direct result of selection choices made by breeders and rewarded by consumers. Reform requires both supply-side change (breeding associations revising conformation standards) and demand-side change (consumers choosing health over extreme appearance). The most impactful individual action is refusing to purchase from breeds with extreme welfare-compromising conformations.