[header] How to treat macaw wasting disease [title] Recognize gastrointestinal and neurological symptoms of pdd. [step] Macaw wasting disease or proventicular dilatation disease (pdd) can be recognized by a range of digestive and nervous system malfunctions. Your bird may start regurgitating food or simply look very depressed. 
In some species, such as macaws, the gastrointestinal symptoms show up first and it takes a while for neurological symptoms to arise. In cockatoos, you see the neurological signs first.