Tussis in Dogs
The act of coughing serves as a protective mechanism for preventing the accumulation of secretions and foreign materials inside of the respiratory tract, but coughing can also serve as an early warning sign for respiratory diseases. Coughing is generally a symptom of an underlying problem, such as a respiratory or cardiovascular system disease.
This automatic and involuntary behavior is one of the most powerful reflexes in the body and is essential for keeping the pharynx and airways free of accumulated secretions and foreign material. This is, therefore, a normal response to any invasion, obstruction, or abnormality of the airways. The medical term for coughing is tussis, and this condition can be found in dogs of all ages and breeds.
Symptoms and Types
- Sudden collapse
- Coughing up blood may be seen in certain diseases or with prolonged and violent coughing
- Respiratory tract diseases including tumors, infections (viral, bacterial, and parasitic)
- Aspiration pneumonia (pneumonia due to entrance of stomach contents or ingested food particles in the respiratory tract)
- Foreign bodies in the respiratory tract
- Cardiac diseases
For your veterinarian to establish an initial diagnosis, you will need to provide a thorough history of your dog's health, recent activities, and onset of symptoms. Sneezing and coughing can often be confused with each other, so your veterinarian will evaluate your dog's cough to determine if it is really a cough or a sneeze. The sounds can be very similar, so closer attention will need to be paid. Obvious outward differences may show the mouth staying closed during the reflexive action, indicative of a sneeze, whereas with cough, the mouth is opened.
The pattern and frequency of the cough are very important in determining the cause of the cough. Your veterinarian will ask you about the duration, timing, pattern, frequency, and characteristics of your dog's cough, so it can be helpful to both you and your doctor if you make notes of your dog's symptoms before you see your veterinarian.
Your veterinarian will need to evaluate whether the cough is productive or non-productive, so a cough will need to be artificially initiated by your doctor. In productive coughs, secretions, fluid, and mucous may be expelled from the airway, whereas with non-productive coughing or dry coughing no such material comes out with the cough. As coughing is associated with a number of diseases, a careful diagnostic workup is essential for establishing the diagnosis.
After the history and initial physical examination have been done, your veterinarian will take a complete blood count, biochemistry profile, and urinalysis to be analyzed in the lab. A complete blood count may suggest the presence of infections or allergies, based on the amount of white blood cells that are present in the blood, and a blood biochemistry test may show abnormally elevated liver enzymes or other abnormalities that are related to the underlying cause.
If your dog is also experiencing nose bleeds or is coughing up blood, tests related to blood clotting will be conducted to determine whether blood clotting mechanisms in the body are working normally. Other diagnostic tools that may be used include radiographic studies, such as X-rays, computed tomography (CT) and magnetic resonance imaging (MRI), all of which can be extremely valuable in determining the cause of the cough.
For a closer and more detailed view of the respiratory tract, your veterinarian may also use a laryngoscope, tracheoscope, or bronchoscope for a direct visualization of the various parts of the upper tract. Fecal testing may also be conducted to check for the presence of respiratory parasites in the body and your dog will be tested for heartworm disease, which can also lead to coughing in affected dogs. Your veterinarian can also take fluid samples from the respiratory system for further evaluation, since some types of parasites will remain on the walls of the respiratory tract.