Signs and Symptoms of Pneumonia in Dogs

Pneumonia is a progressive condition that can severely affect a dog’s breathing ability. Lung tissue contains alveoli, small clusters of air sacs. As the dog breathes in, air fills these sacs. Cells and small blood vessels in the lining of the alveoli exchange oxygen from the air with carbon dioxide, which the dog exhales. When bacteria, viruses, or fungal organisms invade the nostrils or trachea, they can cause an infection. This infection causes inflammation inside the air sacs in the lungs. In addition to the swelling, pus, and fluid take up additional space. This allows less room for air to fill the lungs and causes respiratory distress for the animal.

Although both dogs and cats can become ill with infectious pneumonia, dogs are more susceptible. It can develop as a bacterial, viral, fungal, or parasitic infection of the lungs. An infected dog can spread the bacteria or virus by simply touching noses with another dog. A dog’s sneeze or cough launches pneumonia pathogens into the air. Dogs with bacterial or viral upper respiratory infections may develop pneumonia if these infections are not treated.

The bronchi are large air passages that transport air to and inside of the lungs. The term “bronchopneumonia” is the scientific term for pneumonia. There are many different causes for bacterial pneumonia, but these causes are all traced back to a bacterial infection. In most cases, exposure starts with inhalation of the bacteria or pathogen. However, the infection can also spread through blood, but this is less common. Bacterial pneumonia is often a secondary infection to severe kennel cough or other upper respiratory infections. It can also develop as a result of aspiration of food or a foreign object into the lungs. There isn’t a single pathogen that causes pneumonia. However, researchers have identified two organisms commonly found in dog’s with bacterial pneumonia: Bordetella bronchiseptica and Streptococcus zooepidemicus.

It is sometimes difficult to distinguish viral from bacterial pneumonia. This type of pneumonia is usually the result of viral infections such as canine distemper, parvovirus, canine influenza virus, or upper respiratory infections. Kennel cough can also be a viral infection. These viruses cause damage to the dog’s airways, which makes them more susceptible to the development of pneumonia. Like bacterial pneumonia, viral pneumonia spreads easily from dog to dog.

Also known as a mycotic infection, fungal pneumonia is a lung infection that can result from exposure to several types of fungi. These include Blastomyces, Histoplasma, and Aspergillus. In most cases, dogs contract this type of infection after coming into contact with soil that is rich in organic matter, bird droppings, or feces. It may develop over a long period of time. Some of these fungi enter the body through the nasal cavity; others enter through mouth inhalation. Certain breeds are more susceptible to this type of pneumonia. Male German shepherd dogs are two to four times more likely to be infected.

There are several reasons why a dog may develop aspiration pneumonia. In most cases, the dog aspirated or inhaled their food, foreign bodies, vomit, or regurgitated gastric acid. Aspiration can lead to inflammation and infection of the lungs. Bottle-fed, newborn puppies are at higher risk of developing pneumonia. Dogs with specific health conditions requiring forced feedings are also at a higher risk. General anesthesia can trigger an infection. Dogs who inhale cigarette or cigar smoke, kerosene, gasoline, or other chemicals are more likely to develop aspiration pneumonia. However, vets say the most common cause is poor administration of liquid medications using a dose syringe or stomach tube.

Sometimes dogs are victims of serious accidents, such as a car hitting them. A traumatic chest injury can lead to pneumonia. These types of injuries often cause inflammation in the lungs in addition to the visible trauma. Pulmonary contusions, or bruises, can cause pneumonia, but veterinarians don’t usually prescribe antibiotics to prevent it. There is a risk of resistant bacteria overgrowing and developing into pneumonia. Vets don’t usually treat dogs for pneumonia unless they first confirm its diagnosis.

Two of the most obvious signs of pneumonia in dogs is a deep, soft cough. Sometimes the cough sounds wet or crackly. Heavy, labored breathing, or rapid breathing are primary symptoms. The dog may appear to be in respiratory distress. Some dogs have a yellow, green, or bloody nasal discharge. The infected dog doesn’t seem interested in eating and tends to be lethargic or fatigued. Weight loss is not unusual. Fever is usually present with fungal pneumonia but doesn’t always appear with bacterial pneumonia. Additionally, lameness occasionally occurs in dogs with fungal pneumonia. Dogs with aspiration pneumonia may also have swallowing difficulties and a bluish tinge to the skin.

Dogs often require hospitalization so that veterinary personnel can monitor the animal’s breathing and administer medications. The dog may need supplemental oxygen. Veterinarians always treat pneumonia with antibiotics. They may even prescribe multiple types of antibiotics. Veterinarians prescribe nebulizer treatments using antibiotics or airway dilators to treat the lungs. The fine mist created by the nebulizer allows better penetration by the lungs, which loosens the mucus. The vet may also perform coupage, a method of tapping the dog’s chest to break up the mucus. Brief exercise helps the dog to cough up the mucus.

Owners should vaccinate dogs against the viruses that cause pneumonia. Avoid places where dogs congregate or areas that have had previous outbreaks. If you board your dog, verify the facility’s procedures for preventing kennel cough and other infectious conditions. Don’t allow your pet to socialize with a dog if it is coughing or showing other symptoms of illness. If your pet is showing signs of pneumonia or another illness, keep your dog away from other animals. Smoking in the house and using aerosol sprays can lead to aspiration anemia in pets. Air purifiers may help prevent some exposure to household irritants, especially if they have health conditions or are recovering from pneumonia.