Thoroughbred Pedigrees Show Little Genetic Diversity

More than 95% of Thoroughbreds share the same paternal lineage, and almost half of the genetic makeup of the breed can be attributed to just 10 foundation horses. These facts are just a few of the recent findings brought to light by a research


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Rebecca Splan, MS, PhD, has more than 20 years of horse experience, working with a variety of breeds and disciplines. She is the Assistant Professor of Equine Science in the Department of Animal and Poultry Sciences at Virginia Tech. In 1998, Dr. Splan lived in Dublin, Ireland, researching genetics of Thoroughbred racehorses prior to completion of her Ph.D. Both in and out of the office, Dr. Splan continues to be heavily involved in horse community. She is often asked to speak regionally or nationally on topics related to conformation and selection of performance horses, and is delighted to contribute to a variety of youth events annually. She is an open horse show judge, USDF L graduate and is certified in equine appraisal. In her free time, she enjoys campaigning her Half-Arabian mare in dressage and sport horse divisions. Dr. Splan also serves on the Board of the Southwest Virginia Dressage Association and Virginia Arabian Horse Association.

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