Independent inquiry into dog breeding - Bateson

http://breedinginquiry.files.wordpre...iry-120110.pdf

Makes interesting reading

Unquestionably inbreeding can lead to a loss of
biological fitness. The animals in the inbred lineage
are less likely to survive and less likely to reproduce
than animals in more outbred lineages. This has been
demonstrated many times in well-studied, naturally
outbreeding species. Inbreeding can result in reduced
fertility both in litter size and sperm viability, developmental disruption, lower birth rate, higher infant
mortality, shorter life span, increased expression of
inherited disorders and reduction of immune system function. The immune system is closely linked
to the removal of cancer cells from a healthy body
(Smyth et al., 2006), so reduction of immune system
function increases the risk of full-blown tumours.
Many of the effects of inbreeding have been found
in isolated populations of wolves, the wild ancestors
of domestic dogs, with detrimental effects (Laikre
& Ryman, 1991). Severe inbreeding depression
has been documented in Scandinavian wolves that
had passed through an extreme bottleneck (Liberg
et al., 2005). During their first winter after birth the
number of surviving pups per litter was strongly and
inversely correlated with how inbred were the pups.
The more inbred they were, the less likely were they
to survive. Given what happens in wolves, domestic
dogs should be no exception to the rule that breeders
should avoid close inbreeding as much as possible

And all litters available around same time

I know of a dog, whose parents are brother and sister. They are both Westie x Cairns... that is so wrong IMO

Does anyone know the answer to the question? Or is it subjective?
I know many people seem to feel Grandparent/Grandchild is ok....but parent/offspring not.....

How about Aunt/nephew or 1/2 sister/1/2 brother?