An offering at the upcoming Keeneland yearling sale is inbred to the dam of A.P. Indy, which inspires a quick look at the Rasmussen Factor pattern of Thoroughbred inbreeding.

The Comparable Index is a tool that helps evaluate how strong a stallion's book of mares is -- either from year to year, or compared to other sires in a given year. It has many applications -- and I include an example of how commercial breeders might benefit with a bit of smart prospecting.

Getting back to basics: What is the Average Earnings Index?

Several five-cross pedigree examples will help illustrate this overview of inbreeding in Thoroughbred bloodlines. By the time you're through, I hope you can spot an error on one of the reports.