Delayed gastric emptying in dogs can be a worrisome condition considering that it signals a malfunction in the correct functionality of a dog's stomach. In order to better understand what happens, it helps to take a closer insight into how the dog's stomach works, how it processes food and how the food is moved from the stomach to the intestinal tract. Veterinarian Dr. Crnec provides information about delayed gastric emptying in dogs and what happens at the vet's office with dogs diagnosed with this condition.
How a Dog's Stomach Works
A dog’s stomach is relatively large, which is ideal for an animal that feeds and scavenges opportunistically. Dogs are ambitious eaters. When food is available, they will eat much more than they actually need – and they have the stomach to store it.
A dog’s stomach has a considerable capacity to expand when food is plentiful. It can hold between 4 to 10 fl oz (100-250ml) of contents per 2.2 Ib (1 kg) of a dog’s body weight.
This means that a Labrador Retriever’s stomach has a capacity of up to 14 pints (8 liters). Any Labrador owner knows the dog will use this stomach capacity to its limit, which is why many owners say that a Labrador is a life-support system for a stomach.
The stomach is a reservoir for mixed and predigested food, a holding tank where hydrochloric acid and certain enzymes, under the control of gastrointestinal hormones, are secreted.
Gastric acids begin the process of breaking down the food for digestion. Muscular waves in the stomach mix and move the food, contributing to its breakdown, before it is passed into the intestines, where digestion is completed and the molecular components of food are absorbed.
The Process of Gastric Emptying in Dogs
Gastric emptying is the physiological process of delivering food to the small intestines. The rate of gastric emptying is determined by the intensity and frequency of tonic contractions of the stomach’s muscle layer.
As a highly regulated process, the gastric emptying rate can be altered by many physiological, pharmacological and pathological factors. There are three types of gastric emptying or motility disorders in dogs:
- Accelerated motility – the muscular contractions occur too frequently
- Decreased motility – the muscular contractions do not occur frequently enough
- Retrograde transit – the food moves in the opposite direction. This can be gastroesophageal or entero-gastric.
Sadly, gastrointestinal motility disorders are becoming more and more common among canines. Decreased emptying, popularly known as delayed gastric emptying, is the most frequently seen motility disorder in veterinary practices worldwide.
Delayed Gastric Emptying in Dogs
Delayed gastric emptying is an acquired condition that usually develops secondary to an underlying gastrointestinal issue. It can be defined as prolonged passage of food from the stomach to the duodenum (the first portion of the small intestines). Under normal circumstances, the stomach is emptied 6 to 8 hours after eating.
When a dog vomits undigested food 12 hours after its last meal, it is clinically suspected for delayed gastric emptying. Once food is retained in the stomach for longer than necessary it leads to distension, bloating and further delay in the food transit.
The delayed gastric emptying can be primary or secondary. The primary delayed gastric emptying can be idiopathic (when the cause is not known) or due to electrical misfirings in the stomach’s muscle layer.
The secondary delayed gastric emptying can be due to a plethora of underlying conditions: such as stress, nervousness, pain and trauma, stomach issues such as gastric dilatation, inflammation, bloat, blockages, infections (parvovirus) and stomach surgeries. In these cases, the condition is termed as functional delayed gastric emptying.
Other causes include blood disorders – low potassium levels, high urea levels, metabolic disorders – sluggish thyroid gland (hypothyroidism), autonomic nervous system issues and certain drugs.
When it comes to delayed gastric emptying there is no breed or sex predisposition. However, the condition is more common among aging dogs than in young puppies.
What are the signs of delayed gastric emptying in dogs? The exact clinical picture depends on the underlying cause. However, the most commonly observed signs include:
- A dog vomiting undigested food
- Loss of appetite
- Abnormal appetite (compulsive eating of non-food)
- Stomach distension
- Weight loss
At the Vet's Office
The diagnostic process begins with obtaining a detailed history about the dog’s eating and eliminating habits, dietary and exercise regimen and complete health and vaccination status. The next step is physical examination. Its goal is to determine the exact underlying cause.
More often than not, the physical examination requires some additional tests such as:
- Blood analysis – complete blood cell count and biochemical profile to evaluate the: kidneys, liver, total protein, blood sugar status, electrolytes.
- Urinalysis – to evaluate the kidneys and the hydration status
- Fecal analysis – to rule out parasites as an underlying or associate cause
- X-rays and ultrasound of the abdomen – to rule out blockages and presence of foreign bodies and to determine the rate of gastric emptying (contrast radiography)
- Gastroscopy – to rule out mechanical obstructions of the stomach
- MRI – allows simultaneous and non-invasive assessment of the gastric emptying and motility rate.
- Exploratory laparotomy – if the other diagnostic procedures are inconclusive.
Treatment for Delayed Gastric Emptying in Dogs
There is no set treatment protocol for patients with delayed gastric emptying. Each patient requires an individually tailored approach. Most patients with delayed gastric emptying do not require hospitalization. They would be initially treated and then sent home. However, daily check-ups are recommended until full recovery.
Some uncomplicated cases can be fully resolved with simple dietary changes. Liquid and semi-liquid diets promote easier and faster gastric emptying. It is also recommended to give frequent but small volume meals.
Other cases require medical treatment with different types of drugs. The commonly used medications include:
- Antiemetics – to reduce the vomiting frequency
- Antacids – to reduce the acid production (beneficial in cases when the underlying cause are gastric ulcers)
- Gastrointestinal protectants – to protect the irritated intestinal lining
- Adsorbents – to neutralize the harmful agents
- Promotility drugs – to promote gastrointestinal movement.
Stomach surgery is performed in cases of obstruction. The aim of the surgery is to remove the blockage and repair the surrounding tissues if damaged.
What's the prognosis for delayed gastric emptying in dogs? Both the recovery length and the prognosis depend on the underlying cause and the dog’s responsiveness to treatment. Dogs that respond to dietary gastric promotility treatment will fully recover in just a week or two. However, to prevent recurrence, the newly implemented dietary regimen must be continued. All in all, the prognosis is excellent.
In cases of surgical management, it may take up to 10-14 days for the stomach to regain its normal function and motility. Nevertheless, the prognosis is good.
For cases in which the underlying cause is abnormal function of the autonomic nervous system the prognosis is grave.
For further reading:
- Ask the vet: Is there any acid reflux diet for dogs?
- Ask the vet: Is there a bland diet for a dog's upset stomach?
- Types of Stomach Cancer in Dogs
- Dog with Stomach Cancer Not Eating
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 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.