Southdown sheep sustainable gene pool. Mock continued his extensive search, and by 1990, he was able to find a total of 350 of the Southdown sheep that had the original bloodlines, and many of them still carried their original Southdown registration papers recognized by the UK. At that time, Mock started the first and original Olde English Southdown Registry to market this once meat breed to a completely new market for people looking for pets and 4H projects, and he started the "Babydoll" used by the members of the original registry, as well as the few spin-off Babydoll registries. When Mock and
Breed registry stud book is a stud book or breed registry that does not accept any outside blood. The registered animals and all subsequent offspring trace back to the foundation stock. This ensures that the animal is a purebred member of the breed. In horses, an example of a closed stud book is that of the Thoroughbred, with a stud book tracing to 1791. The American Kennel Club is an example of a kennel club with primarily closed books for dogs; it allows new breeds to develop under its Foundation Stock Service, but such dogs are not eligible for competition in AKC