WHICH BIRDS ARE MOST AT RISK?
Psittacine beak and feather disease is caused by a circovirus and mainly affects species from Australia and Africa, including budgerigars, cockatoos, lovebirds and African greys. Eclectus and lorises are also commonly affected. The virus can affect birds of all ages, but young birds are most at risk. The incubation period varies according to the age of the bird. In young birds, the disease develops very quickly, over 2–4 weeks. In older birds, the infection tends to be more chronic and the incubation period varies from a few months to a few years. However, once clinical signs appear, life expectancy is, on average, 6–12 months.
TRANSMISSION
Infected birds shed the virus into the environment through their feces, regurgitation/vomiting, or feather dander. A bird can become infected by ingesting the virus, but also by inhalation (airborne transmission). Transmission from parents to offspring also appears to be possible. This mode of transmission is currently being studied. In addition, transmission by indirect contact, i.e. through objects or even by humans who have been in contact with an infected animal, is possible.
CLINICAL SIGNS PATHOGENESIS
The virus induces necrosis of the basal epidermis as well as necrosis, clots and hemorrhages in the feather pulp. This results in deformed, fragile and easily shed feathers. The virus also attacks the germ cells of the beak, causing necrosis.
- Red feathers of abnormal distribution in African Greys
- Delayed molt
- Dull plumage, fragile, frayed feathers deformed feathers
- Abnormal loss of feathers Little/no powder on feathers, itching
- Hyperkeratosis/Elongation of the beak (especially in cockatoos).
- Longitudinal cracks may eventually appear.
- Necrosis of the beak and the mucous membrane of the palate.
- Beak pain.
- Lethargy Regurgitation
The virus is also found in the blood, where it attacks white blood cells and thus causes a decrease in the immune system (immunosuppression). The bird therefore becomes susceptible to various diseases and infections of all kinds.
DISEASE DETECTION
We can detect the virus in the blood using a PCR (polymerase chain reaction) test, even before any symptoms of illness appear. Alternatively, we can perform the test using a dystrophic blood feather, though this method may be less reliable than the PCR test. All of these tests are conducted in-hospital after a thorough examination of the bird.
DISEASE CONTROL
As there is no specific treatment for Feather and Beak Disease (FBD), and it is often fatal, it is highly recommended to have any new bird tested for the disease. This is especially important if you have multiple birds at home or if the bird could come into contact with other birds, such as when boarding or visiting. PCR testing is also advised if the bird's origin is unknown, questionable, or poses a potential risk.
Strict hygiene measures are essential to prevent significant contamination, and thorough disinfection of the environment is crucial. Before disinfection, a thorough cleaning should be done. Although the exact stability of the virus in the environment is not fully understood, it is believed to be highly resistant and difficult to eliminate. A 10% bleach solution or iodine can effectively disinfect, but many common disinfectants will not work. Currently, there is no vaccine for FBD. Ideally, avoid using food, toys, and materials from areas where untested birds are present.