Hi everyone, I have a question. I have a green-cheeked conure, 17 years old, named Baby. Since December he's been developing some black spots on his feathers followed by breakage of those same feathers. I've been taking him to the vet every other week for the last 4 months, and they don't seem to understand what's causing it. No lice or mites, but they treated him anyway. He's been given a run of antibiotics. He has a healthy and diverse diet, but now the breakage and black spots are spreading. It first started on his right wing, and now it's spread to both. I don't know what to do.
His eating and playing habits don't seem to have changed at all, though he's begun flapping his wings for no apparent reason. Any ideas would be helpful and greatly appreciated. Thank you.