In horse breeding, Blood Percent and AGR are two different methods used to measure the degree of Thoroughbred bloodlines in a horse.
Blood Percent refers to the percentage of Thoroughbred bloodlines in a horse. It is calculated by dividing the number of Thoroughbred ancestors in the horse's pedigree by the total number of ancestors in the pedigree, and then multiplying by 100. For example, if a horse has 10 Thoroughbred ancestors out of 16 total ancestors in its pedigree, its Blood Percent would be 62.5%.
AGR, on the other hand, stands for "Adjusted Generation Regression". It is a statistical method that uses a horse's pedigree to estimate the percentage of Thoroughbred bloodlines in a horse. AGR takes into account the number of generations in a horse's pedigree, and assigns more weight to the more recent generations. It also takes into account the number of ancestors in the pedigree who are known to have Thoroughbred bloodlines, as well as the degree of their Thoroughbred heritage. AGR can produce a more accurate estimate of a horse's Thoroughbred bloodlines than Blood Percent.
In general, Blood Percent is a simpler method for estimating Thoroughbred bloodlines, while AGR is a more complex and potentially more accurate method. However, both methods can be useful in evaluating a horse's breeding potential and predicting its racing or performance abilities.