A dog’s esophagus is the muscle that connects the stomach to the throat. When the dog swallows food, the esophagus allows that food to travel to the stomach, contracting and pushing the food down the esophagus as it goes. Megaesophagus in dogs is a condition in which the esophagus is enlarged, and its motility, the ability to move food, is reduced or entirely absent. This is a very distressing condition because the dog cannot consume or digest food, and it could lead to other complications such as aspiration pneumonia.
Causes of Megaesophagus in Dogs
The causes of megaesophagus in dogs are largely unknown. It is congenital in nature, meaning that many dogs are born with it. Wire haired fox terriers and miniature schnauzers are two breeds that have shown to be at higher risk for congenital megaesophagus. Other breeds predisposed to the condition are German shepherds, dachshunds, great Danes, Irish setters, Labrador retrievers, pugs, and Chinese Shar-Peis.
The cause of acquired megaesophagus, or the condition that develops later in life, is also largely unknown, but it’s been suggested that it might be due to:
- A neuromuscular disease such as myasthenia gravis, distemper, or myositis
- A tumor on the esophagus
- Foreign body stuck in the esophagus
- Inflammation of the esophagus
- Ingestion of poison such as lead or thallium
- Parasitic infections
Symptoms of Megaesophagus in Dogs
If your dog is suffering from megaesophagus, the first clue will be that they regurgitate any food or water that they try to consume. This is because, due to the lack of motility in the esophagus, the food won’t have anywhere to go once the dog tries to swallow it. It’s for this reason that dogs suffering from megaesophagus might develop aspiration pneumonia, when food or liquid finds its way into the lungs.
In addition to regurgitation, dogs with megaesophagus may also show other symptoms including:
- Nasal discharge
- Loud breathing, strange noises during breathing
- Weight loss
- Extreme hunger
- Anorexia, or lack of appetite
- Excessive drooling
- Bad breath
- Poor or stunted growth
Diagnosing Megaesophagus in Dogs
If you suspect that your dog has megaesophagus, or you notice that they’re regurgitating, it’s important to take them to the vet immediately. If your dog can’t eat food, their system will break down and they could become malnourished very quickly.
The vet will want a complete medical history, focusing on digestion, esophagus, and throat issues, as well as the most current symptoms they’ve been exhibiting. They will then perform a complete physical examination, and will need to determine if the dog is vomiting or regurgitating. This is important because if the dog is regurgitating, the vet will be able to rule out conditions that cause vomiting. The vet will also carefully exam the regurgitated material looking at the presence of undigested food, and length of time from ingestion to regurgitation or vomiting to differentiate between the two.
The vet will likely order or perform a number of tests including a complete blood count (CBC), biochemistry profile, and a urinalysis. These will not only help identify the presence of megaesophagus, but can also determine if aspiration pneumonia is present, which is a common complication of megaesophagus.
If the vet suspects megaesophagus, they will need to exam the actual esophagus. In order to do this they will perform an esophagoscopy, which will include inserting an esophagoscope into the tube. This instrument is thin and tube-like itself, and has a lens and a light attached to it. These allow the vet to physically exam and observe the inner areas of the esophagus, identify the problem and possibly, correct it. Esophagoscopes can also be used to remove foreign objects that are causing the blockage.
Treating Megaesophagus in Dogs
In order to treat megaesophagus, the underlying cause must first be treated. If a foreign object is stuck in the esophagus, surgery might be needed to remove it if it can’t be done with an esophagoscope. This will be done immediately to prevent further complications and to allow the esophagus to function normally again.
If parasitic infection is the reason for the condition, deworming medications might be prescribed or other antibiotics that will help eliminate the infection. If the dog has developed aspiration pneumonia – an extremely common complication of megaesophagus – they may require immediate hospitalization, oxygen therapy, antibiotics, and other medications.
During the course of treatment, it’s important to remember that the dog is unable to eat and therefore, not getting nutrients. The vet may recommend a special diet that may include foods such as liquid gruel, small meatballs, pureed slurries or milkshakes, and other high-energy foods. If this diet can’t be consumed by the dog, they may need to be put on intravenous fluids to provide them proper nutrients.
Living with megaesophagus is not easy for the animal or the person taking care of them. They require plenty of soft bedding and sometimes need to be turned every four hours. If the dog still cannot eat on their own, they may require a feeding tube which the vet can show you how to operate at home. You will also need to regularly weigh your dog to ensure that they’re gaining weight, but also not gaining it too rapidly.
If the dog is able to eat on their own, they’ll still require some help. They will need to be held in an upright position for 10 to 15 minutes after eating, and food and water bowls need to be raised 45 to 90 degrees from the floor. This will help correct or prevent aspiration pneumonia.
In most cases, megaesophagus in dogs requires life-long care and a great deal of commitment. You will need to take your dog into the vet for regular visits to evaluate the condition and the progress of their treatment. If aspiration pneumonia develops or is suspected, thoracic radiographs will also be taken. Sadly, dogs suffering from congenital megaesophagus or megaesophagus due to an unidentified cause have a very poor prognosis. Most dogs are lost to complications such as aspiration pneumonia.