Join Date: Nov 2009
Location: Erie PA
Mentioned: 0 Post(s)
Quoted: 1 Post(s)
Thanked 1,782 Times in 466 Posts
Not to get too technical on you but there are certainly reasons to be linebreeding on certain dogs. As other posters have mentioned, this is a very common practice and a great-grandmother in common is not a very close breeding. How close the breeding is though and the COI would actually be determined by how many times an actual dog shows up in a pedigree.
There are actually times that a breeding doesn't seem close at all when looking at a COI(coefficient of inbreeding) because the COI is determined again by how many times one dog shows up in the pedigree. You can have closely related dogs-siblings in the pedigree many times and this will not be reflected in the COI.
I do not think your dog's health will be adversely affected by having a great-grandmother in common.
We have actually done breedings closer than that with some of our dogs with linebreeding on our Bailey who is now over 15 years old and still in very good health along with having good clearances, temperament and good breed type. So, you WANT a dog like that to have more influence in your pedigrees. But, at the same time, you still have to allow for enough diversity in the pedigree so that deleterious genes do not show up. I hope that is making sense.
However, even when doing that, our COI's are still rather low(because the rest of the breeding is more an outcross) and in the middle teens and under 20%. I absolutely agree with Sally's mom that a dog with a COI up in the mid 30's and I have seen higher, is really not enough diversity in the pedigree.