Thank you for the great answers.
As I said before , the Feather picking is the most frustrating condition seen in pet birds from both the veterinarian’s and the owner’s perspective—and most likely from the bird’s perspective too! It is important for you as an owner to understand that feather picking is a symptom, not a particular disease. What your avian veterinarian needs to do is determine the underlying cause of feather picking and address this problem in addition to the feather-loss. In this way feather picking is like diarrhea or coughing--there are many things, which can lead to picking. Known causes of feather picking include: improper diet, use of mite guards in the cage, not enough bathing, cedar bedding, low humidity, smoking, environmental items causing allergies, other bird aggression or improper mutual grooming techniques, boredom, fear, attention-getting, poor wing trims, damaged feathers, trauma, cancer, viral infections, bacterial infections, fungal infections, parasites (rare), molting problems, skin problems, liver disease, kidney disease, low blood calcium, and hormonal effects. As you can tell, this is a huge list and needs to be narrowed down!
Unfortunately there is no one treatment or medication will do the work. This bird needs to be seen by an Avian Veterinarian. Have you tried this hospital ? http://rahkwt.com/info/avian.php
Your avian veterinarian can narrow down this list of possible causes of feather picking by performing testing and treatments step-by step or all at once. These steps can include: 1. A detailed, complete history taken by the doctor and/or staff 2. A thorough physical examination 3. Modifications to the diet as needed 4. Corrective wing trim(s) as needed 5. Separating the feather picker from other birds 6. Eliminate exposure to environmental allergens 7. Increase bathing 8. Blood work (red and white cell count, biochemistry panel, liver function testing) 9. Gram’s stain cytology and fecal parasite testing 10. Infectious disease screening (e.g. psittacine beak and feather disease virus, avian polyomavirus) 11. Lead and zinc blood level testing 12. Thyroid hormone level screening 13. X-rays 14. Skin/feather biopsy 15. Behavior counseling with an avian behaviorist
You can always send a drop of blood sample / or feather sample to one of these laboratories for sex determination