According to The Daily Puppy, dogs are known to sometimes eat their dead puppies. Cannibalism has been observed in dogs, but it is not commonplace. In theory, other dogs of any breed or mix are capable of eating their puppies, dead or alive.
Some breeds of dogs kill puppies due to the erratic movements and high-pitched sounds of some puppies being reminiscent of mice and other rodents. Mother dogs operate on instinct, seeing stillborn or unhealthy puppies as a danger to the rest of the litter. This has been observed to lead to the mother eating stillborn puppies or killing and eating unhealthy ones.