Horse breeding practices including warmblood selection, Thoroughbred racing genetics, and draft breed health affect the welfare of millions of horses across generations.
Horse breeding decisions made by humans for performance, appearance, or commercial purposes have profound long-term welfare consequences for the horses produced. Thoroughbred selection for speed has concentrated genes for lean muscle mass and large heart capacity alongside genes for skeletal fragility — contributing to the catastrophic fracture rates seen in racing. Draft breed selection for extreme pulling capacity has created horses prone to lymphedema. These are not accidents but predictable consequences of single-trait selection without welfare constraints. Responsible breeding requires integrating welfare traits — structural soundness, metabolic health, longevity — into selection criteria alongside performance. Breed registries that implement health testing and reject stallions with significant heritable health problems demonstrate that welfare-conscious breeding is achievable.