An enlarged esophagus in dogs is something that needs veterinary attention because it can cause a variety of complications. The causes of an enlarged esophagus in dogs can be various and therefore affected dogs require diagnostic tests so to tackle the underlying cause. Symptoms of an enlarged esophagus in dogs are often readily noticed noticed by dog owners because they tend to be quite evident. Following is some information about an enlarged esophagus in dogs from veterinarian Dr. Ivana Crnec.
A Lesson in Anatomy
The esophagus is a muscular tube through which food and liquids, once swallowed, are transported from the throat to the stomach. Swallowed mouthfuls of material do not simply move passively along the esophagus, but are actively pushed and squeezed along by rhythmical contractions of its muscular walls.
These movements, which are not under conscious control, are called peristalsis. Aided by the lubricating mucus produced by the walls of the esophagus, these movements effectively drive food toward the dog's stomach, independent of the force of gravity. This explains why a dog can stand and eat or drink with its head down.
Unfortunately a variety of problems can develop with a dog's esophagus. A relatively rare, but demanding and complicated issue is a condition known as megaesophagus or enlarged esophagus.
Megaesophagus is a known inherited trait in certain lines of miniature schnauzers and wirehaired fox terriers. Megaesophagus also occurs with increased incidence in the following breeds: Chinese shar peis, German shepherd dogs, great danes, Irish setters, Labrador retrievers, dachshunds and Newfoundlands.
Causes of an Enlarged Esophagus in Dogs
Why does the dog's esophagus enlarge? What exactly is megaesophagus in dogs? Megaesophagus is defined as partial or generalized enlargement of the esophagus that leads to either decreased or absent peristalsis.
When a section of the esophagus fails to contract, or it is partially blocked by a foreign body, food cannot properly progress to the stomach. Instead it collects at the point where the blockage occurred, thus forcing the esophagus to expand.
Megaesophagus can be inherited or acquired. It is considered an inherited condition in certain breeds, while in older dogs it is an acquired condition.
Common causes of megaesophagus include neuromuscular conditions such as distemper, myositis, myasthenia gravis, a foreign body in the esophagus, esophageal tumors, esophageal inflammation, parasitic infections, intoxications (thallium, lead). Unfortunately, in most cases, the exact cause cannot be determined.
"In endemic areas, such as Kansas and Missouri, dysautonomia should also be considered as an underlying cause for megaesophagus, with 61% of dogs with dysautonomia documented to have radiographic evidence of megaesophagus."~Dr. Kate KuKanich, board-certified veterinarian specializing in internal medicine.
Symptoms of an Enlarged Esophagus in Dogs
A dog suffering from enlarged esophagus will show a plethora of symptoms such as regurgitation, weight loss, changes in appetite either under the form or extreme hunger or anorexia, poor growth, disabled swallowing, coughing, respiratory distress, nasal discharge, excessive drooling, bad breath and changed vocalization.
The hallmark symptom of megaesophagus is regurgitation. It is important to make a difference between vomiting and regurgitation. Vomiting is an active process usually associated with retching or heaving. On the flip side, regurgitation is a passive process that occurs without warning signs.
Simply put, a megaesophagus is similar to a deflated balloon. It collects food and water up until it cannot keep collecting. At that point, the dog regurgitates the recently swallowed content.
Aspiration pneumonia is a common and life-threatening complication associated with enlarged esophagus. This occurs because the food trapped inside the esophagus can easily enter the lungs.
It should be noted that in many cases the enlarged esophagus is not a diagnosis itself, but rather a symptom of some other disease.
At the Vet’s Office
In order to set a differential diagnosis your veterinarian will take your dog’s full history, ask you about the signs and symptoms you noticed and perform a full physical examination. The best way to confirm the diagnosis is to take an X-ray. Additionally, performing a blood biochemistry test can help determine possible causes.
The ideal therapeutic approach would be to treat or eliminate the underlying cause. For example, if the cause was a foreign body, a surgery to extract the clogged object will be performed.
A diagnosis of meagesophagus was a death sentence in the past. Luckily, with the advancements in the field of veterinary medicine, today, if properly taken care of, dogs with enlarged esophagus can live long and quality lives.
However it should be noted that these dogs require life-long therapy, regular follow-ups at the vet’s as well as commitment and strict feeding regimen.
Feeding a Dog with Enlarged Esophagus
Dogs suffering from enlarged esophagus require specifically tailored feeding schedule and regimen. The goal of the feeding regimen is to meet the dog’s nutritional requirements and to get the food and water out of the esophagus and into the stomach as quickly as possible.
To successfully manage a dog with enlarged esophagus, few guidelines need to be followed. One important one is feeding the dog in an elevated position. By elevated position we mean a truly vertical position. The vertical position puts the esophagus in the right orientation for the gravity to work. The vertical feeding position can be accomplished by using specially designed chairs. The dog needs to remain in the chair for 20-30 minutes after eating or drinking.
Providing multiple but quantitatively small meals throughout the day is important, it is advised to give at least 3 to 4 meals per day. Meals should consist of high-quality and calorie-dense food. This is important because it reduces the volume of the food while meeting the dog's daily nutritional requirements.
The consistency of the food is also important and influences the success of the management. Foods fed in a "milkshake’’ consistency or "meatball’’ size and shape have shown to work best. Dog owners should be diligent in preventing the dog from accessing food and water outside the monitored and controlled feeding time.
Veterinarians will also prescribe medications. Medications for an enlarged esophagus in dogs usually include acid reducers, 1 or 2 times per day to minimize acid production, and motility drugs to aid the stomach emptying, and thus, prevent gastroesophageal refluxes.
- Dog esophagus anatomy, by BaileyMartin15 - Own work, Wikipedia CC BY-SA 4.0, edited to add anatomical name
About the Author
Dr. Ivana Crnec is a graduate of the University Sv. Kliment Ohridski’s Faculty of Veterinary Medicine in Bitola, Republic of Macedonia. She is a certified nutritionist and is certified in HAACP food safety system implementation.
She currently practices as a veterinarian in Bitola and is completing her postgraduate studies in the Pathology of Domestic Carnivores at the Faculty of Veterinary Medicine in Zagreb, Croatia.
Ivana’s research has been published in international journals, and she regularly attends international veterinary conferences.