If you let the bitch take care of the pups, why the heat lamp in summer, what your saying and what I see are two different things
My bitches on average most always have 5 or 6 pups a litter, must be their inbred depressed...
Inbreeding for the sake of inbreeding, is a dead end road. There must be quality and constitution there for the need or want of it, anything less and you'll send yourself backwards into this depression you spoke of. The signs will tell you when you've gone to far. that's why you always leave your self a way out to breed. The example of the Branko/patch cross to start my line, if I get week in one area, i breed out to the Branko or patch to pick up what I need and go right back to work on my line again. It's why you bring two families together to start you line, so you have a reliable backcross to go to and get what you need from established families that have longevity on their side proving quality is there.
Hope your litter stays large and healthy, 9 puppies is alot for mama to keep track of...