Respiratory problems in dogs could be a sign of something that needs to be taken care of. Sneezing is common and normal; however, if you notice other symptoms, or abnormal breathing, it could signal a more serious situation. Here are some medical issues that can affect the lungs and cause breathing problems for a dog.
Kennel Cough
Kennel cough, or Bordetella, is a mild yet highly contagious disease. It affects the upper respiratory and may develop into fatal bronchopneumonia or chronic bronchitis in puppies and debilitated adult dogs. Because there are so many possible causes of kennel cough, the vaccine doesn't always work well. Some factors which may increase susceptibility are stress, humidity, and temperature.
In order for a dog to get kennel cough, he needs to inhale the bacterias, so he is more likely to contract it if he is in an enclosed place where he is in close contact with many dogs.
Respiratory Cancer
Cancer starting in a respiratory system is less common than forms of cancer which start in other organs of the body. It is, however, common for tumors to form in the lungs from cancers that have spread from other areas of the body. Of the cancers that occur in the respiratory system, the most common occurs in the nasal sinus passages.
Pneumonia
Pneumonia, an inflammation of the lungs, is more common in dogs than it is in cats. Bacterial and fungal infections are the most common types of pneumonia. Dogs with pneumonia often show signs of coughing, difficulty breathing, loss of appetite, fever and depression.
Fungal Infections
There are various types of fungal infections which cause respiratory problems for dogs. Aspergillosis affects the nasal chambers and is most common in young dogs, especially breeds with long noses. Symptoms include sneezing, nasal pain and lethargy. If not treated, the fungus may progress, destroying the spongy nasal passages and continuing to grow into the cranium and around the eyes. Cryptococcosis is a systemic disease which affects the respiratory tract, eyes, skin and central nervous system. This fungus is most commonly found in soil and fowl droppings. The infection first shows up as lesions on the face, legs and lungs and may rapidly spread to the central nervous system. Once the brain is involved, there is little success with treatment. Histoplasmosis is another systemic fungus which grows in the soil of more tropical areas such as the Ohio River Valley and Appalachian Mountain range. This disease is non-contagious and some forms are mild. Blastomycosis is a fungus usually found in the Mississippi River area, around the Great Lakes and areas in the south where soil is moist and rich in decaying vegetation. Dogs most affected by this type of fungus seem to be young hunting breeds. Valley Fever is found in the dry areas of the southwest US and northern Mexico. This fungus in not highly contagious and most dogs develop an immunity to it, never showing outward signs of the illness. Hunting dogs and dogs with a lowered immune system are particularly at risk.
Tracheal Collapse
When the trachea, the windpipe, collapses the dog starts to gasp for air, cough and gag. Some possible reasons for this are genetic, birth defects, trauma and degeneration of the cartilage (mainly in older dogs). Old, middle-aged and small breeds are the most commonly affected.
Laryngeal Paralysis
The larynx, or voice box, is located in the throat and connects the mouth and nasal passages. The muscles attached to the larynx may become paralyzed, as a result of a dysfunction of the nerves to the throat, causing breathing difficulties. The reasons for this occurring are unclear but may be caused by damage done by kennel cough germs, excessive barking, choke chains, excessive pulling on the leash or getting objects stuck in the throat. Symptoms include noisy breathing, intolerance to exercise, coughing, gagging, vomiting and sometimes an inability to breath.
Asthma
Asthma is a rare condition in dogs in which the air passages to the lungs fill with mucus, swell and begin to spasm, limiting the amount of air reaching the lungs. Canine asthma is characterized by wheezing usually related to allergies and hereditary dispositions of different breeds. Other symptoms are coughing and gasping for air as if he can't catch his breath.