The Thoroughbred racehorse is a hybrid animal which has considerable variation in both its genotype and its typology. Each racehorse has a genetic profile that traces back to lineages common to the very origins of the breed. From these confined roots, the ancestral condition of the Thoroughbred horse has diverged into many racing aptitudes and levels of talent. The challenge to every breeder is to recognize how the variations of individual performance can be maintained and transmitted to succeeding generations. We need help in understanding the historical narratives that are found in the pedigrees of horses we breed.
Pedigrees are genetic codes.
They consist of many ancestors some especially valued for exemplary racing achievement or their ability to pass on favorable traits. Only highly valued ancestors and their best representatives can meet the exacting criteria of quality demanded to help upgrade for racing performance. Indisputably, every two or three generations working lines from these superior individuals tend to fade. No matter what the accomplishments from racing or breeding programs, nature smoothes out all inconsistencies that deviate from the accepted norm. In an attempt to counteract this slide toward mediocrity, we can give a brief description of four methods of breeding Thoroughbreds.