It looks like he's growing feathers in feathers, but the feathers have failed to erupt from their sheathes. This is creating the quill-like appearance, but what you are actually seeing is the sheath that growing feathers are encased in. Sometimes, birds just are unable to get the sheathes off of their feathers. I know that some of my chickens can have trouble with their neck feathers, as they can't reach those feathers to pull off the sheathes. My males in particular sometimes have this problem. I've never seen a case as severe as yours, though.
Use your fingers, and grip the feathers near the base. Then, slide your fingers up each encased feather. This should remove the sheathes, and the feathers should start filling out normally. One of my friends has a rooster that always has feather sheath problems when he grows in his feathers. My friend solves this problem by putting his rooster in with hens. The hens strip away all of the sheathes.
Hope I've helped!
