(1)Your bird might be going through a molt. If his feathers are hard and encased in what looks like soft, opaque plastic, thyey are new feathers which are coming in. If they are normal feathers then I think I would need to see a photo of your bird to help you further.
(2) A sick bird is one who:
If you think your bird is sick, please crank up the heat to around 80 degrees F (27 C), and increase the humidity to make the room almost steamy. Lower the perches and pad the cage floor should he fall. Make sure his food and water is within easy reach, and call your vet (www.aav.org/vet-lookup) for an appointment.
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