Line breeding question - Page 1

in my opinion when line breeding to any particular dog i would usually say that 3-3 is close enough but what about 2-4 which in a blood sense equates to the same as 3-3 would like to here your thoughts on this it is not about any one dog or kennel just a thought on line breeding
jim h

I don't hold much faith in this method of evaluating inbreeding levels jim.  You need to look at the pedigree in depth and take account of background inbreeding that exists in all breeds, and use the COI calculation as a method of determining inbreeding levels.

For instance, your examples - 3:3 and 2:4 both give a COI  of 3.13%, without taking account of any background inbreeding.  If you compared this with a pedigree of say 2:2 on one dog, it might appear that the first two examples have lower inbreeding, but if they happened to have a higher level of background inbreeding their COIs could actually be higher than the 2:2 dog.

The recommendation now, to avoid inbreeding depression, is to calculate COI back to 10 generations and this should be no higher than 6.25%.  I don't know much about modern GSD pedigrees but I guess this would not be easy to accomplish consistently within the modern show type bloodlines.

Linebreeding can be a valuable tool. As with any breeding selection of parents that have and are known to produce certain and desired traits should be selected.  In breeding we do not just look at what we are doing in one generation..but ahead with directions for the future.

Yes, I do feel it can be a valuable .

 Yes, POD is correct in the correct method for COI..

JMO
Debi
www.webtarts.com/sherman-ranch

What did we ever do before calculators I wonder.
I've only linebred one time a sire back to his grand daughter.   I just knew the dogs.
Not knocking your system, just don't believe it's a science I subscribe too.

thanks all for your input so far
jim h

Hi Jim
my two WG showline COI over 10 gens are 3.7% and 5.6%
Pam