Offspring´s

[elf]

What is normaly a healthy % of COI ???

Depends... because first it's needed to breed away for harmful alleles, only then one can breed for diversity. On the other side it has been proved many times higher inbreeded dogs lived some years less than lower inbreeded dogs (same for genetic diseases incidence).
Nowadays for the CsV, breeders should try to be less than 10% on five generations (as this is the mean value on 5 generations).