What would make a feather grow in as transparent instead of solid?

Not sure where to put this. I have a bird who just molted and the feathers came in very transparent. The center of the feather is solid but the rest is see through. What would cause this? Will this fix itself with added vitamins to water? Will I need to wait for another molt? Anyone ever notice anything like this?

 

These are not pin feathers. I will go take a pic. He went through a very hard molt, every new feather that came in, came in the same way, on his wings, his neck, his back, everywhere. While they were coming in, he was on a med but the med never listed that it would affect new feather growth. I guess my main question about it is with the proper diet and added vitamins, could these feathers correct themselves?

Here are some pics. The first pic is the wing feathers near the shoulder. The one on the left is correct, the one on the right is his, the transparent one.



This pic is the neck feather. Again, the left is correct, the right is the transparent one.



This is not just one feather that this happened to, it is every single one, everywhere.

 

He was on Nystatin for a possible fungus type problem and then Flagyl for canker. Can this be corrected without another molt?