I remember someone saying the % is like mating relative a to relative b, if the COI is 22% whats this and how is it worked out many thanks

Ah a complex subject :)
The inbreeding is computed as a percentage of chances for two alleles to be identical by descent. This percentage is called "inbreeding coefficient".

Typical inbreeding coefficient percentages are as follows, assuming no previous inbreeding between any parents:
Father/daughter, mother/son or brother/sister  25%
Grandfather/granddaughter or grandmother/grandson 12.5%
Half-brother/half-sister, Double cousins 12.5%
Uncle/niece or aunt/nephew  12.5%
Great-grandfather/great-granddaughter or great-grandmother/great-grandson 6.25%
Half-uncle/niece or half-aunt/nephew 6.25%
First cousins  6.25%
First cousins once removed or half-first cousins  3.125%
Second cousins or first cousins twice removed  1.56%
Second cousins once removed or half-second cousins  0.78%
Third cousins or second cousins twice removed 0.39%
Third cousins once removed or half-third cousins  0.20%

As many pedigrees will have animals that are line or inbred themselves the calculations of COI can be complex and computer programmes are needed. A pedigree that doesn't look too closely related over first few generations can actually be quite inbred if calculated over 10 or 20 generations.

Rare breeds will generally have greater COI due to restrictions in breeding populations however popular sires can result in higher COI over time in popular breeds.

For me I consider COI alongside many other considerations such as health, temperament, work ability, type etc.

Thanks, there is an email from AHT circulating in Dogues and contacting owners of those with a 12.5% and over, average is 6% many with a percentage greater than that seem to have already gone to rainbow bridge. mine are 1% 3% and 5%, just wondering. will bookmark this for reference.

My aunt has recently bought a toy pup and when she showed me the pedigree I was shocked to see alot of names repeated. When I searched the kc site the coi is 37.5% breed average is 9%. Puppy seems bright and healthy but how will/could this affect the puppy?

great post too, thanks

Inbreeding does not "cause" defects however if there are genetic health issues in the bloodline then inbreeding increases the chance of demonstrating those issues as there is a far greater percentage chance of inheriting the faulty gene from both parents.

Closely bred animals MAY have issues associated with inbreeding depression such as shorter life span, lower fertility, highly strung temperaments and reduced size and substance.

The key is knowing what is in the line before line or inbreeding, no room for rose tinted glasses or sentimentality. I have used both line and inbreeding and had large healthy litters with good quality pups BUT you have to know when new blood is needed and NEVER take risks with health. A high COI for me is not an issue if the breeder is knowledgable and can explain why the mating is close and explain what they hope to achieve.

If the parents are healthy you are more likely to have healthy pups. Therefore, if this pup is healthy now I wouldn't worry too much. One of mine had a very high COI as she was from a mother/son mating (an accident) and she lived til she was 13, as did her daughter. I have a grandson here who had his 11th birthday on Sunday has only seen the vet for a broken toe. He still does his best to keep up with my 22 month old dog (same breed) and is still very fit and healthy.