My finches are losing their feathers

Question
I have two white headed nuns. One started losing feathers on his whole head.
We exposed in him to more sunlight, cleaned his cage and checked his
progress. The other finch was fine. When that didn't help, we sprayed the
cage and finches for mites. Our parakeet in a neighboring cage has no
unusual feather loss yet. It's been two days and the bald finch started
growing his feathers on his head back, but now his chest is losing feathers
and it's happening to the other finch's chest as well. Please advise on
treatment.

Answer
Hello,

I am not a veterinarian. Any health concern need to be discussed with your avian veterinarian. i recommend you make an appointment immediately. Do not continue to try and treat their condition yourself. Without a proper diagnosis you may make the condition worse.

Jennifer