Dyspnea in Birds
Dyspnea is labored or difficult breathing. Animals who are dyspneic appear to be in distress or discomfort. They usually have an increase in respiratory rate, or tachypnea, and breathing may or may not be labored. Although diseases of the respiratory tract often cause labored breathing, other disease, such as heart disease, nervous system disorders or mechanical disorders may cause dyspnea or tachypnea.
Dyspneic birds usually breathe with their mouths open. Breathing may require a whole body effort, manifested by "tail bobbing," where the tail moves up and down with every breath. In some birds, a squeaking noise can be heard with each inspiration.
Some birds have unique behaviors that may be mistaken for dyspnea. For example, cockatoos often hiss when excited or frightened. African grey parrots make a growling, gurgling tracheal noise when captured and restrained. Pionus parrots make a distinct wheezing noise when excited.
There are many causes of dyspnea and tachypnea. Some of the most common include:
- Respiratory disease – pneumonia, air sac infections, allergic pneumonitis, tracheitis
- Toxins – inhaled teflon fumes, carbon monoxide
- Obstruction of the trachea – inhaled seeds, tumors, abscess, goiter
- Compression of the air sacs – enlarged abdominal organs, ascites (fluid accumulation in the abdomen), neoplasia (cancer)
- Cardiac disease
- Nervous system disorders – brain trauma, neoplasia
Birds have an extremely efficient respiratory system and generally do not become dyspneic or tachypneic until disease processes are well advanced. Any bird that appears to have difficulty breathing should be seen by a veterinarian.
What To Watch For
- Open mouthed breathing
- Whole body excursions with every breath or "tail bobbing"
- Lethargy, sitting with feathers fluffed up
- Excessive sleepiness
- Weakness – birds that are too weak to stay on a perch are in critical condition
Your veterinarian will recommend specific diagnostic tests depending on how severely dyspneic the bird is and based on physical examination findings. Since several different respiratory and non-respiratory diseases may cause dyspnea and tachypnea, extensive diagnostic testing may be necessary.
A complete history is extremely helpful in reaching a diagnosis. Be prepared to tell your veterinarian when the problem began, any other symptoms you've noticed, the type of diet your bird is on and any exposure to other birds.
Diagnosis May Include
- A thorough physical examination, including auscultation (listening with a stethoscope)
- Radiography (X-Rays) to evaluate the lungs, air sacs and abdominal cavity
- A complete blood count (CBC) and serum biochemistry panel
- Blood tests or choanal samples for Chlamydiosis (Psittacosis) or Aspergillosis
- Endoscopy – viewing the trachea, air sacs or lungs with a rigid endoscope to collect samples for biopsy or culture
- Sampling the trachea for bacterial culture and cytology (looking at cell types for evidence of infection or inflammation)
Treatment May Include
Treatment for dyspnea and tachypnea may include any combination of:
- Placing the bird in an oxygen cage
- Antibiotics or anti-fungal medications
- Nebulization with humidified air and antibiotics or anti-fungal medications
- Severely dyspneic birds or those with other clinical signs in addition to dyspnea usually require hospitalization for 24-hour care.
Dyspneic birds require veterinary attention. After seeing the veterinarian, be sure to:
- Give all medication as directed, for as long as directed, even after the symptoms appear to be gone.
- Watch for a change in breathing, and report any changes to your veterinarian.
- If improvement is not seen, report this to your veterinarian.
- Keep the bird in a separate room from birds that create a lot of feather dust (cockatoos, cockatiels, African grey parrots).
- Do not smoke cigars or cigarettes around the bird.
In mammals, breathing is accomplished by excursions of the diaphragm, which increases the volume of the chest, thereby drawing air into the lungs. Birds do not have a diaphragm, and the lungs do not expand and contract with respiration. Instead, large air sacs fill the thoracic (chest) and abdominal cavity. Birds use their breast and abdominal muscles in order to breathe. Contraction of these muscles expand the volume of the thoracoabdominal cavity, thereby inflating the air sacs, and drawing air past the lungs for oxygen exchange. If the abdominal cavity contains an enlarged organ, a tumor or excess fluid, there may not be sufficient room for expansion of the air sacs. If the air sacs cannot expand fully, air cannot be drawn past the lungs, and the oxygen exchange is insufficient. Birds with space-occupying lesions in the abdominal cavity will often become dyspneic or tachypneic. Occasionally, the space-occupying lesion will be contained within the air sacs in the form of exudate or fungus. This is most often seen with Aspergillosis, a fungal respiratory disease.
This concept should also be considered whenever a bird is restrained. If held too tightly around the chest, the bird cannot expand the thoracoabdominal cavity. It may become very difficult for a bird to breathe when improperly restrained. Very small birds, such as canaries and parakeets, could potentially suffocate.
Birds have an extremely efficient respiratory system, which is an adaptation for prolonged, rigorous exercise such as long flights. However, most pet birds do not exercise very much, spending most of their time sitting in cages or perches (activities requiring very little oxygen expenditure). Because of this, dyspnea and tachypnea are usually not seen until diseasel processes are quite advanced. Therefore, if you notice labored respiration in your bird, veterinary attention is immediately warranted.
The advanced efficiency of the avian respiratory tract can sometimes have deadly consequences. Exposure to gases and aerosolized fumes that are often relatively harmless to other species can be acutely fatal to birds. For example, inhalation of fumes from over heated Teflon and other non-stick pans can cause a fatal acute pneumonitis. Birds will die quickly following exposure to carbon monoxide. (You may be familiar with the practice of coal miners bringing canaries into the mines. The sudden death of these birds served as a warning of toxic gas concentrations). In general, all aerosolized sprays should be used with caution, or avoided entirely, around pet birds.
There are many respiratory and non-respiratory causes of dyspnea and tachypnea in birds.
Respiratory Causes Include
- Bacterial pneumonia – including chlamydia and mycoplasma, which are potentially zoonotic
- Aspergillosis – a fungus normally found in the environment which can cause severe, life-threatening pneumonia or air sacculitis in pet birds
- Viral pneumonia
- Aspiration pneumonia – accidental inhalation of food or liquids into the lungs
- Allergic pneumonitis – seen in some bird housed with birds that produce large amounts of feather dust (cockatoos, African grey parrots)
- Pulmonary edema – fluid accumulation in the lungs
- Toxic – inhaled Teflon fumes, aerosol sprays, cigarette smoke, carbon monoxide
- Tracheal obstruction – inhaled foreign bodies (esp. seeds), papillomas (warts), neoplasia (tumors), abscesses, granuloma
- Tracheal compression – neoplasia, abscess, granuloma, goiter (in budgerigars)
- Upper respiratory tract obstruction – tumors, abscesses or foreign bodies in the nasal cavity or choana
- Air sacculitis – accumulation of exudate or fungus in the air sacs from bacterial or fungal infection
Non-respiratory causes of dyspnea and tachypnea may include:
- Compression of the air sacs – Ascites (fluid accumulation in the abdominal cavity), hepatomegaly (enlarged liver), neoplasia (cancer), peritonitis (inflammation of the lining of the abdominal cavity), egg binding (retention of eggs in the uterus), severe obesity
- Congestive heart failure – may cause fluid accumulation in the lungs (pulmonary edema)
- Central nervous system disorders – trauma, brain tumors, encephalitis (inflammation of the brain)
- Anemia – blood loss or decreased production of red blood cells
- Acid/base disorders – secondary to metabolic diseases such as diabetes mellitus
The veterinarian will recommend specific diagnostic tests depending on how severely dyspneic your bird is, how long the problems have been going on and physical examination findings. As dyspnea and tachypnea may be caused by several respiratory and non-respiratory disorders, extensive diagnostic testing may be necessary. Any combination of the following may be recommended:
- Radiography (X-Rays) are needed to evaluate the lungs, air sacs and abdominal cavity. Usually, the entire thoracoabdominal cavity is radiographed. Radiographs may reveal pneumonia, pulmonary edema, air sac disease or space-occupying lesions in the abdominal cavity. The bird must be held completely motionless, so general anesthesia is often used.
- A complete blood count (CBC) is needed to look for evidence of infectious disease, allergies or inflammation. Certain types of white blood cells will be elevated in number with specific diseases. Many types of infectious diseases, such as Chlamydiosis and Aspergillosis have characteristic patterns of white blood cell increases.
- Serum biochemistry panel is needed to look for evidence of metabolic problems, such as diseases of the liver, kidney or pancreas.
- Blood tests (Serology) or choanal samples for Chlamydiosis. These tests look for the body's response to the organism causing Chlamydiosis (antibodies), or for the presence of the organism itself (antigen).
- Serology for Aspergillosis
- Endoscopic examination of the choana and/or trachea. Tumors, abscesses, granulomas or foreign bodies may be detected by directly visualizing these areas. Specialized equipment is required, and this procedure is usually performed by an avian specialist.
- Tracheal wash – sampling the trachea for bacterial culture and cytology (looking at cell types for evidence of infection or inflammation).
- Endoscopic examination of the air sacs – By directly viewing the air sacs, the veterinarian can assess the severity of disease and collect biopsy specimens for histopathologic examination and culture. Additionally, biopsy samples may be obtained from the lungs if indicated. The entire abdominal cavity can be visualized through the endoscope, making it possible to obtain samples of enlarged organs or some tumors as well. This procedure is performed by an avian specialist.
- Sampling of the nasal cavity or choana for bacterial culture or cytology. Samples may be taken directly from the nostril after dried material has been removed, or by flushing the nostril out with saline (salt) solution, or by removing some cells through a needle (fine needle aspirate).
- Serum protein electrophoresis – Certain protein fractions (gammaglobulins) circulate in the blood with many infectious diseases. Analyzing the types of proteins that are elevated in circulation will aid the veterinarian in the diagnosis of these diseases.
- Abdominocentesis – If fluid is present in the abdominal cavity, samples may be obtained via a catheter for analysis.
There are many causes of dyspnea and tachypnea, and the cause must be identified for proper treatment. Your veterinarian may recommend one or more of the diagnostic tests described above. In the meantime, treatment of the symptoms is needed, especially if the problem is severe. The following treatments may be applicable to some, but not all birds that are dyspneic or tachypneic. These treatments may reduce the severity of symptoms, or provide relief for your bird. However, nonspecific therapy is not a substitute for definite treatment of the underlying disease responsible for your bird's condition.
- Dyspneic birds, especially birds with additional symptoms such as lethargy and anorexia usually require hospitalization and 24-hour care.
- Birds with severe dyspnea require oxygen supplementation, and are placed in an oxygen cage.
- If the trachea is obstructed, it may be bypassed by placing a small endotracheal into the abdominal air sac. The bird can temporarily breathe through this tube, while the obstruction is being cleared.
- Nebulization with humidified air, antibiotics or antifungals may be needed in birds with respiratory tract disease.
- Cleaning dried exudate or secretions from the nasal cavities and/or sinuses may often be accomplished by flushing the sinuses with a saline solution. If the material is dried, it may be cleaned out with forceps under magnification. This process sometimes requires general anesthesia.
- Antibiotics or antifungal therapy is often given both systemically (by mouth or injection) and topically (by instilling antibiotics directly into the trachea).
- Birds that are dehydrated may require fluid therapy, administered by injection under the skin (subcutaneous) or intravenously.