What happen to the nine puppies that napoleon takes away?

Napoleon takes the nine puppies from their mothers as soon as they are old enough- he takes them into a separate room from all the other animals where nobody can see them, and Napoleon says he is educating them.

However, in a later chapter, we discover that he did not educate them, but trained them as attack dogs. He then uses them to make animals agree with him, as the animals are scared of these dogs.