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Open vs Closed Studbooks

Did you know? Open vs Closed stud books. I almost forgot that I said I would address this topic in another post so here it is, this isn't specific to PMs but still great information to get a better understanding of purebred dogs. First off what is a "Stud book", a stud book is the collection of pedigreed data for a breed. The pedigree database is an unofficial studbook, what this means is that it is just a collection of pedigrees that can openly be edited by the public to work together to keep a worldwide collection of data. Official stud books are managed by kennel clubs such as AKC, RSCE, FCPR, ANKC, etc. Some of these kennel clubs have public databases to view the data in the stud books. Others do not. We have actually started creating a list of pedigree databases that we find that are public during our research of breed history in various countries:

Now, what is an open stud book vs a closed stud book. Lets start with a closed studbook because it is one we are primarily familiar with in the US. AKC is considered a closed studbook even if a studbook is marked as "open" for a particular breed because even when it is open, once a breed is fully recognized the dog still needs a complete 3 generation pedigree. Closed stud books do not allow for an animal without a pedigree to be registered. In the US you cannot simply look at a dog say it is a Pyrenean Mastiff and have it registered, their is no process or procedure for this as it isn't allowed. Kennel clubs also do not recognize breed testing like that of Embark as a means to judge register-ability of a dog. There are major downsides to a closed studbook. The big one is that over time you lose genetics and nothing new is added so the base genetics of a breed shrink over time. Here is a great example that shows how a closed stud book can affect a population:

In an interview shared a couple weeks ago with Rafael Malo Alcrudo he talked about a genetic depression and the effects of it on the breed. This often has to do with no new genetics being introduced to a gene pool or the gene pool getting smaller quickly as mentioned in the article above. Here is study on the impacts:

Now not all stud books are considered closed stud books, closed stud books was only introduced about 100 years ago. The opposite to closed stud books is of course open stud books. Open stud books allow dogs to still be added to the studbook even if they do not have pedigree information. Depending on the situation and conditions of an open stud book there are processes and procedures for a dog to be added to the stud book. In Pyrenean Mastiffs there is an open stud book in Spain and in order for a dog to be added they must be evaluated by a breed specialty judge no earlier than 1 year of age to see if they meet the breed standard and phenotype. Some kennel clubs in various countries even have protocols for out crossing projects to other breeds to help bring in new genetics to a breeding population. In the article above it talks about how a gene pool never gets larger it can only get smaller within a closed stud book. The only way to increase the size of a gene pool is to have an open stud book that allows you to introduce new dogs to the gene pool that are genetically diverse to the existing gene pool.

While the Pyrenean Mastiff is in AKC FSS status we have a semi open stud book. This means dogs still must have at least parents on record, we cannot go pick up any dog who looks like a PM and register it in the US but we could register a dog with an export pedigree from Europe who does not have a complete 3 generation pedigree.

Now, inbreeding and line breeding etc are not inherently bad, purebred dogs are all inbred to some degree and the inbreeding is what makes all Pyrenean Mastiffs look alike. Line breeding when done correctly can help lock in physical traits while inbreeding helps to maintain a breed's type. Line breeding isn't for the novice breeder, it should be something only done by those who have extensive knowledge of their lines as line breeding while producing beautiful dogs can also cause lots of recessives to pop up that can impact health. So if you aren't familiar enough with the health of the line you are line breeding on it is best to hold off until you do extensive research.

Puppy picture for attention!

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