How long does a dog stay at a pound before it is killed?

In high kill animal shelters, the dogs are kept for a maximum of 9 days before they are euthanized. they give a 9 day frame either for the rightful owner to claim the animal back or to see if it can be adopted. Sadly, most of the animals are euthanized. Especially, pregnant dogs and small puppies are euthanized right away. They have absolutely no chance of survival in these shelters.