Cropout

A cropout, crop-out or crop out is a horse with body spots, including pinto or leopard complex spotting, or "high white" horse markings, with a sire and dam who both appeared to have been solid-colored. There are several variations in the definition, depending on the breed registry involved. There are multiple genetic reasons that may cause a horse to be a cropout. Sometimes solid-colored horses throw cropouts because some spotting patterns are recessive genes that are not necessarily expressed unless the relevant allele is inherited from both parents. Other times a gene may be a dominant or incomplete dominant but so minimally expressed that the horse looks solid but can pass flashy color on to its offspring

The term originally came about because excess white in certain breeds was considered an undesirable trait and such foals were deemed ineligible for registration, making them grade horses of little economic value. However, many people liked the flashy color, others sought to keep cropout horses from becoming worthless, and thus new breed registries formed, such as the American Paint Horse Association. In recent years, as DNA testing has become available to verify parentage, breed registries that once excluded cropouts are now accepting them.

The term "cropout" is today most closely associated with horses of American Quarter Horse breeding. These horse are often registered as American Paint Horses, where the term usually refers to horses with overo coloring and whose parents were solid horses not registered with the APHA. It may also refer to sabino-patterned horses. For a cropout horse to be registered as a Paint, both sire and dam must either be Quarter Horses registered with the AQHA, or Thoroughbreds registered with The Jockey Club, plus have coloring that qualifies it for the regular registry of the APHA. Since the AQHA modified its "white rule" to allow registration of cropouts as Quarter Horses, the APHA has also limited its registration of cropouts to those foaled prior to January 1, 2005.

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