Since our friends across the pond have never had dilutes show up, their open stud book seems to be irrelevant. It is strictly a North America problem.Hi Meredith,
Just a note. The British Kennel Club allowed retriever crossbreds and interbreds until at least 1937. Interbreds were crosses between the retriever breeds recognized at that time. For instance, a Labrador would be bred to a golden retriever (quite common). The puppies from that litter would be registered as Interbreds. One of those pups could then be bred to another purebred, registered golden, and be registered as a purebred golden.
Crossbreds consisted of a retriever breed bred to another breed or do who wasn't a retriever. Many times the non-purebred was not registered. Those crossbreds would then be registered, bred back into purebred lines, and eventually be registered as purebreds.
I am in no way saying this produced a dilute gene or was the background of silver Labradors. I am NOT an advocate of silver labs. But thought you might find this interesting that the English Kennel Club allowed this type of breeding and registry up until, I believe, the start of World War II. (I have some English Kennel Club stud books listing registrations of these retriever interbreds and crossbreds.)
So, in the third generation, these interbreds or crossbreds would be registered as a purebred. If someone imported one of these dogs to the U.S., the Kennel Club would provide the official export pedigree and the dog could be registered with the AKC as a purebred.
I found this pretty fascinating.