Is this ethical breeding?

[andrew113]

I've been talking at length to a borzoi breeder who seems really great in every way. Experienced with the breed, checks all the boxes in what to look for in a good breeder. However, I just found out that for the upcoming litter— the one I was planning to get a (companion) puppy from— the parents are siblings. Is that a normal thing to do? I asked the breeder about health effects of inbreeding like that, and the breeder said that genetic tests were run before deciding to breed them. Both the parents are national champions, so I guess the breeder wanted to maintain some traits? I am new to this, so I wanted to see if the inbreeding situation is as concerning as it sounds?

 

[lutece]

A sibling breeding is inbreeding. The actual amount of inbreeding involved, however, depends on what is behind the parents, and if they are inbred themselves. It is theoretically possible for a sibling mating to have less inbreeding than a mating of two dogs that don't have any obvious repeats in a three generation pedigree... it will depend on the rest of the pedigree.

Since this breeder sounds like a good breeder in other ways, you could ask a little more about the breeding plans and the overall coefficient of inbreeding for the litter. When the breeder said that they ran genetic tests, it's also possible they ran tests for genetic diversity and the expected diversity of the puppies. Ask all the questions you have about their breeding methodology. Most serious breeders love to talk about about why they make breeding decisions.

 

[lutece]

For example, here is the UC Davis VGL genetic diversity testing page for Borzoi, along with a research report on the breed:

Genetic Diversity Testing for Borzoi

Overview The Veterinary Genetics Laboratory (VGL), in collaboration with Dr. Niels C. Pedersen and staff, has developed a panel of short tandem repeat (STR) markers that will assess genetic diversity across the genome and in the Dog Leukocyte Antigen (DLA) class I and II regions. This test panel...

vgl.ucdavis.edu

If you read the population structure portion of the report, you will see that the Borzoi that were tested for this report can be clustered into different genetically distinguishable, related groups:

Now let's say that you are evaluating the potential genetic diversity of a litter of puppies in which the parents are siblings.
That pedigree is going to look something like this:

The question is, how closely related are the grandparents A and B?

If A and B are very closely related, like this, the overall pedigree is going to have relatively low genetic diversity:


However if A and B are very unrelated, like this, it's possible that the overall pedigree may have higher genetic diversity than average for the breed, even though the parents are siblings:


That's why I would suggest having a deeper conversation with the breeder about the litter plans, and the type of genetic testing that was done.

• It's possible there is not as much "inbreeding" in this mating as it might appear, if the breeder is doing genetic diversity testing that shows the potential sibling mating to have good genetic diversity, or pedigree analysis that shows this sibling mating to have a relatively low COI.
• On the other hand, some breeders really do tolerate a lot of inbreeding in their breeding programs, and it's possible there is also lots of inbreeding behind the grandparents in the pedigree. Close line breeding / inbreeding is a choice made by some breeders. You might still want to work with this breeder, if you feel comfortable with their level of experience with the breed. If you're not comfortable, you can walk away and look for a different Borzoi breeder.

I hope that makes sense -- feel free to ask questions if it didn't