The presentation of a macaw with macaw “asthma” can be confusing, and the name is misleading.
Other names for this disease include pulmonary hypersensitivity or polycythemia.
Whatever the chosen name, this is a long recognized disorder in macaws. By the time a macaw has clinical signs of this disease, there has been damage and scarring of the tissue of the lungs. Often the only clinical sign is increased difficulty breathing with exercise. These same signs could indicate heart disease, anemia, an abdominal mass or respiratory infection, either bacterial or fungal.
Your veterinarian may need to perform several diagnostic tests, including a complete blood count, blood chemistries, radiographs (X-rays) and even echocardiology (ultrasound of the heart). A significant elevation in the thickness of the blood is often present. Also, changes on the X-rays may help your veterinarian to diagnose this disease. Even if macaw asthma is diagnosed, secondary bacterial or fungal (aspergillosis) infection may occur and require treatment.
Various allergens have been implicated in causing macaw asthma. The most common association has been with bird species (primarily cockatoos and African greys) that produce aerosolized powder down. Some macaws can co-habit a household area with no resultant problem. However, ideally these bird species should be housed separately. If this cannot be accomplished, the prophylactic use of a quality air filter (such as a HEPA filter) positioned near the cage of the powder-down producing species is recommended for the pulmonary health of the macaw as well as the owners themselves. Many other environmental allergens may be involved, but no consistent agents have been isolated.
The best initial treatment for severe disease is oxygenation. Depending on your bird’s condition, your veterinarian may recommend hospitalization and additional treatment. Long-term management includes removal of the inciting particulate matter – whether that is dust from other birds, or other material – with increased ventilation/HEPA filters. Your veterinarian may recommend drawing blood to thin it allowing better circulation, and/or the use of bronchodilators.
Repeat crisis situations (episodes of severe respiratory distress) may occur and necessitate re-hospitalization and phlebotomy (blood collection). Change of environment and increased ventilation will reduce the speed of disease progression. Some permanent lung damage will be present, and exercise intolerance may persist and worsen over time due to interstitial fibrosis (scarring of the lungs). Unfortunately, some birds cannot be saved.