Puff is a 2-year-old umbrella cockatoo living with Salema and Trevont in Atlanta. She was born in captivity and raised from hatching by Salema's mother until she was about 12 weeks old.

Puff has a very large cage in which she spends nights. Her days are spent outside the cage and throughout the house. She is allowed to fly. Her diet is based on pellets, but she eats a huge variety of foods.

Going back over the past year, Salema reports having noticed abnormal-appearing feathers on Puff's wings.

It started with just one or two and has progressed now to the point where there are many. These feathers are curling and do not have proper length to the shaft. Most recently, it appears Puff is reluctant to fly and, when she does, it's only for short distances. She has not been to her veterinarian yet but has an appointment, Salema says.

I am very concerned about Puff's abnormal feathers. There are multiple possible causes, but one in particular is a progressive process that ultimately ends in death. It is called psittacine beak and feather disease (PBFD).

PBFD occurs in many different species of birds, predominantly within the parrot group, the group we term psittacines. It was first described in what are called Old-World parrots, but this disease can also occur in parrots from the new world. PBFD is a contagious disease caused by a virus called circovirus. It can spread from one bird to another via feather dander and feces.

There can be birds that are carriers of the virus but don't have the disease. These birds can pass the virus to other birds, which contract the infection.

PBFD can manifest itself in an acute or chronic form. The acute form usually occurs in younger birds and is rapidly progressive and fatal. The chronic form may not begin to cause visible symptoms for months to several years after contact. Puff would fit into this category.

With the chronic form of PBFD, the first symptom usually described is the development of abnormal feathers. These feathers are misshapen and usually have retained sheaths with abnormal quills. Often, these feathers will show blood within their shafts. There can be blood in normal feather shafts as they newly develop, but with PBFD, it occurs in abnormal feather shafts. The number of abnormal feathers usually progresses with each molt, which is the term used to describe the normal shedding of old feathers with new ones.

Over time, the beak, and less commonly the nails, can become involved and show distortion in growth and the resulting abnormal appearance. Some of these birds can survive in captivity for years as this disease progressively distorts their feathers and beaks. Eventually, they become so severe they are either euthanized due to poor life quality or they die on their own. Each case progresses at its own pace, which is thought to be dictated by the individual bird's immune response to the virus.

It is possible for a bird to clear this virus and eliminate the disease. This is not common, however, and the prognosis once this disease is diagnosed usually is grave. Diagnosis is accomplished with immunologic blood testing for the circovirus agent that causes PBFD, as well as biopsy of affected feathers. With a positive circovirus test and characteristic microscopic lesions in the feathers, a positive diagnosis for PBFD is made. This is precisely what needs to be done for Puff.

If, regrettably, Puff has PBFD, she can be helped with the secondary issues of the disease. This mainly involves treating the discomfort associated with the disease using anti-inflammatory medications. As long as Puff maintains her quality of life, in my opinion, she should be allowed to keep rolling! We do not know how long that will be.

There are other possible causes for Puff's feather abnormalities, but it is very important to rule out psittacine beak and feather disease. Let's hope her testing results are negative.