At what age does a puppy no longer need to be bottle-fed?

Puppies can be on puppy food as early as four weeks old. They're going to benefit most from their mother's milk, which has the overall support they need for those first several weeks to get proper immunity and have excellent bone strength. And so, usually, by the time they're four weeks old, they don't need to be on puppy milk anymore, or at least not as their sole diet.