A coughing dog is something to pay attention to. A canine cough can have many types and causes, and the underlying problem can range from merely annoying to life threatening. The act of coughing is an attempt to clear the airways, throat or lungs. It can be chronic, frequent or happen only once in a while. To determine why a dog may be coughing, other factors that accompany the cough need to be considered.
A cough can sound like hacking or gagging, be dry or moist, harsh or wheezy. According to the DVM360 website, "a clearer and more treatment-oriented way of classifying a cough is to categorise it into one of three groups: purposeful coughs, warning coughs and nuisance coughs." A purposeful cough does what it is designed to do, get rid of the irritant that created the cough. A warning cough indicates a more serious problem with an underlying issue that can't be ignored. A nuisance cough is caused by something abnormal, such as a collapsed trachea.
Coughing can be a symptom of allergies. Dogs may inhale pollen from trees or grass when playing outdoors, causing the airways to initiate the coughing reflex. The allergens present in the home, be it dust mites, mould or smoke can irritate the dog's air passages.
"Infestation of internal parasites such as roundworms and heartworms can cause coughing," states the Dog Owner's Guide website. Roundworms are found in the dog's intestine. The hatched worms travel through the bloodstream into the lungs moving up the windpipe; this can cause the dog to cough. The heartworm also travels through the bloodstream. According to the Dog Owner's Guide website, "the cough begins when the dog has enough adult heartworms to interfere with exchange of oxygenated blood between lungs and heart."
Also known as infectious tracheobronchitis, kennel cough is caused by bacteria and viruses. A high, dry cough is characteristic of this disease. Kennel cough usually has to run its course, which can last up to two weeks. It is contagious and spread through exposure to other dogs, typically in the kennel environment. According to the Washington State University College of Veterinary Medicine website, "kennel cough usually resolves itself without any treatment."
"The most common type of heart disease in dogs is caused by a malfunctioning (or leaky) valve in the heart. Another form of heart disease, called cardiomyopathy, is caused by a defect in the muscles of the heart," according to Dr. Eric Barchas, D.V.M. Symptoms may include difficulty breathing, blue or purple gums, distended stomach, heart murmur or coughing. The coughing may occur mostly in the morning, at night, or when the dog is excited.