one of the questions asked to me all the time about my dogs is larry you need to outcross you are so line bred you are inbred ...I say yeah but what you think all the rabbits rats and squirrels do they been breeding the same pool for hundreds of years in an area .... a good friend of mine told me one time if you raise enuff chickens you'll have some born without feather's hahahaha .. when mine grow 8 legs and run sideways like a spider i'll cross out hahahaha but mine is perty sound so far ...... hen I have a litter I DO NOT baby them ..and don't breed runts..if you do your asking for trouble .......that's tried and true from nature itself and probably the cause of the panda problem human interference .....
I agree with what you said...
human interference brings a lot of issues because we tend to vaccinate and worm the pups and make warm beds for them in the winter...
on the other hand the coyote bitch must be born with the natural ability to nurture her pups a certain way as well as the sire to help feed the pups not to mention that they sire/dam had top live through disease and then make it on their own once they were wiened...so if we followed the rules of mother nature it would be a different game...survival of the fittest according to the balance or imbalance of nature for that particular time...