Merle is a distinguishing marking of several breeds, particularly the Australian Shepherd and Catahoula Leopard Dog, and appears in others, including the Koolie, German Coolies in Australia, the Shetland Sheepdog, various collies, the Welsh Corgi (Cardigan), the Pyrenean Shepherd, the Bergamasco Sheepdog Old English Sheepdog, American Bully, American Pit Bull Terrier, and Catahoula Leopard Dog. In dachshunds the merle marking is known as "dapple". The merle gene also plays a part in producing harlequin Great Danes and Beaucerons. If the dog was born in or before 2005 is the only way it can have ADBA paperwork. ABKC considers merle a fault. However, they allow the registration and breeding of merle American Bullies.