horses, as a result of the color rule controversy. Based in Missouri, it has a membership of more than 2,000 as of 2008. Other "Appaloosa" registries have been founded for horses with leopard complex genetics that are not affiliated with the ApHC. These registries tend to have different foundation breeding and histories than the North American Appaloosa. The ApHC is by far the largest Appaloosa horse registry, and it hosts one of the world's largest breed shows.

The Appaloosa is "a breed defined by ApHC bloodline requirements and preferred characteristics, including coat pattern". In other words, the Appaloosa is a distinct breed from limited bloodlines with distinct physical traits and a desired color, referred to as a "color preference". Appaloosas are not strictly a "color breed". All ApHC-registered AppaloosasRanger. Appaloosas are crossbred with gaited horse breeds in an attempt to create a leopard-spotted ambling horse. Because such crossbred offspring are not eligible for ApHC registration, their owners have formed breed registries for horses with leopard complex patterns and gaited ability. In 1995 the Nez Perce tribe began a program to develop a new and distinct horse breed, the Nez Perce Horse, based on crossbreeding the Appaloosa with the Akhal-Teke breed from Central Asia. Appaloosa stallions have been exported to Denmark, to add new blood to the Knabstrupper breed.

Health issues

Genetically linked night blindness 

Appaloosas have an eightfold greater risk of developing Equine Recurrent Uveitis (ERU) than all other breeds combined. Up to 25 percent of all horses with ERU may be Appaloosas. Uveitis in horses has many causes,