What Causes Canine Cough?

When a dog starts coughing, it is usually a symptom of an underlying condition that is affecting her respiratory system. But coughing can be caused by a wide range of issues that can be divided into four primary categories: auto-immune issues and inflammatory conditions, infectious agents, geriatric and degenerative conditions, and congenital conditions.

Allergies and asthma are two major cause of coughing in this category. Like humans, a dog can have an allergic reaction to a wide variety of instigators, including certain foods, vaccines, medications, fleas, second-hand smoke, and other environmental allergens.

Asthma, which can affect any age and breed of dog, is more commonly found in younger dogs, and its symptoms usually are at their worst during exercise or periods of very cold or hot weather. When a dog has asthma, she will exhibit an increased difficulty inhaling, which often will produce a wheezing sound. The asthma attack will typically be followed by a coughing outbreak.

Infections can be a result of four types of agents: virus, bacteria, fungus, and parasites. In many cases, canine cough is a sign of a more serious issue, such as an infectious disease like Canine Distemper Virus, heartworm disease, pneumonia, Valley Fever, and of course, kennel cough.

Canine Distemper Virus is a very dangerous disease that can prove fatal because there currently is no cure. There is, however, a vaccination available that will help protect your pet from this infectious disease. Symptoms of distemper include lethargy, coughing, fever, inappetence, tremors, and seizures.

Heartworm disease is caused by an eight- to ten-inch worm that takes up residence in your dog's heart. It then produces microscopic larvae that enter her dog's blood stream. Common symptoms of this disease include persistent coughing, weakness, difficulty breathing, loss of appetite, and weight loss. If left untreated, heartworm can cause heart failure and severe lung disease.

Pneumonia often develops after a dog has suffered through a long bout of respiratory illness or has a suppressed immune system. Along with a persistent cough, symptoms usually include fever, lethargy, loss of appetite, and nasal discharge.

Valley Fever is caused by a fungus that lives in the soil. The spores enter a dog's respiratory tract when inhaled, and once infected, the disease can affect the dog's heart, skin, skeletal system, respiratory tract, and central nervous system. Valley Fever is predominantly found in the southwestern United States.

Of all the infectious diseases related to canine cough, Tracheobronchitis, or kennel cough, is the most common and the least serious. This illness causes the dog to have a dry, hacking cough that's often followed by retching or gagging. Other symptoms include runny nose and eyes, and a reduced appetite.

There are several age-related conditions that can cause a dog to suffer coughing fits, including congestive heart failure, laryngeal paralysis, and certain types of cancers.

Congestive heart failure may affect dogs of any age but typically occurs in late middle age to senior pets. Most commonly this condition is caused by a leak in one of the heart's valves. In some cases, a puppy may be born with a leaky valve, and when this happens, she animal will start showing signs of congestive heart failure much earlier. The most-common symptoms of congestive heart failure are coughing, difficulty breathing and exercise intolerance.

When a dog suffers laryngeal paralysis, it can be hard for her to breathe comfortably because the drapes on the inside of her larynx don't move out of the way when inhaling. This condition is caused by deteriorating function of the laryngeal nerve that essentially paralyzes the larynx. Although this condition can affect any breed, it is most commonly found in large and giant breeds like Labrador Retrievers, St. Bernards, and Great Danes.

Lung cancer is another age-related disease that can cause canine cough. Second-hand smoke is a major predisposing factor. This also may occur as a metastasis from a cancer found in another part of the body.

Some breeds are genetically predisposed to suffering tracheal collapse. This condition most commonly affects brachycephalic breeds, or those with short noses and “pushed in” faces. These breeds include:

• Pugs

• Pekingese

• Japanese Chin

• Boxers

• French Bull Dogs

• American Bull Dogs

• Boston Terriers

• Brussels Griffith

• Puggles (Pug and Poodle Mix)

Congenital causes of canine cough in these breeds tend to start when the dog is still rather young, and in some cases, as young as three years old. Weight also may play a part – if the dog is overweight, then her chance for developing tracheal collapse and canine cough is heightened.