There are over 250 breeds of horses worldwide, with different abilities, temperaments and phenotypic traits that have developed and diversified for thousands of years since horses were first domesticated by humans. This essential textbook describes the basic genetics of the horse including coat color, parentage, medical and population genetics, cytogenetics, performance, breeding systems and genetic conservation, and new advances such as micro-satellite testing. The authors have updated Dr. Ann T. Bowling"s seminal work in light of the sequencing of the complete horse genome, and in addition to the basic genetic principles and their specific applications to the horse, new and revised topics include the development of genomics, gene expression, the relationship of the genome to physiological function, blood groups, transfusion medicine and haemolytic disease of newborn foals. It also includes a greater description of the diversity of breeds of horse in the world, and equid evolution.