The digestive system starts at the mouth, continues through the centre of the body and ends at the anus. In very simple terms it is made up of the mouth, oesophagus, stomach, small and large intestines and rectum. While most of the time it does not cause a healthy dog any problems there are times when it needs some help and support to ensure it makes best use of the food you feed your pet.
To help maintain your dog’s digestive system in good health, monitor your dog's appetite and always know what you are feeding - and what everyone else in the family may be feeding! A good quality complete dog food has the right balance of all the nutrients a dog requires, together with a good level of palatability. Adding human food to a nutritionally complete and balanced commercial dog food may upset the nutrient balance of your dog’s diet. Ideally, table scraps should not be fed - ignore ‘begging behaviour’ for additional food and give lots of hugs and playtime instead. Feed your dog at regular scheduled times and the correct amount to maintain your dog in good body condition.
Any dietary changes should be a gradual process, normally over the course of 7-10 days. Occasional eating and regurgitation of grass can be normal, but generally there should be no vomiting, reluctance to eat or difficulty experienced when eating food. Stools should be a consistent brown colour, firm in texture and passed without any straining, or any blood or mucus (clear jelly) present.
Digestive problems are wide-ranging and can include symptoms such as:
- Loss of appetite
- Excess gas or flatulence
If you notice any changes in appetite or digestion this may be normal, but it could also indicate an underlying medical problem, so if you are worried about your pet’s health seek veterinary advice.
Causes of digestive problems
Gastrointestinal or digestive disorders generally impair a dog’s ability to digest and absorb nutrients. These problems can be caused by a wide range of factors, including:
- Abrupt change in diet
- Indiscretionary eating
- Foreign objects
- Infectious agents such as bacteria, viruses, fungi and parasites
With so many potential causes, diagnosing your dog’s problem can often be a difficult
challenge for your vet. To complicate matters further, the disorder can originate in any part of the dog’s digestive system, from the mouth and oesophagus, to the stomach, liver, pancreas and intestinal tract.
Some problems may resolve once the dog’s digestive system is given a chance to rest. But more serious conditions could result in weight loss, dehydration and debilitation. Your vet will be best placed to advise and determine the appropriate treatment.
Gastroenteritis is an inflammation of the lining of the stomach and intestines. Diarrhoea and vomiting are two of the most common signs of gastroenteritis. Other signs may include loss of appetite or dehydration.
Some of the more common causes of gastroenteritis include:
- Eating inappropriate food or material - for example scavenging through the rubbish bags or bins
- An abrupt change in diet
- Bacterial, viral, fungal or parasitic infections
- Antibiotic therapy. Some antibiotics kill not only harmful bacteria, as they should, but also the normal, helpful bacteria in your pet’s intestine. This imbalance may result in diarrhoea
- Food intolerances
- Food allergy
Reducing the risk of your dog getting gastroenteritis
- Keep an eye on your dog and what he eats, especially when out and about on walks or in the garden.
- Keep rubbish and other ingestible materials out of reach and securely away from your pet.
- When changing diets, transition gradually by adding increasing amounts of the new diet and decreasing amounts of the old over a period of 7-10 days.
The management of your dog’s condition will depend upon its severity. If your dog is dehydrated, fluid therapy may be required. If he is vomiting frequently, your vet may recommend withholding food and/or water for 12 to 24 hours.
Before implementing any dietary change any pet showing signs of vomiting or diarrhoea should be seen by your vet.
Colitis is an inflammation of the colon, also known as the large intestine. Colitis can be acute - beginning suddenly and ending relatively quickly, or chronic - lasting for weeks and recurring periodically. Signs of colitis include blood and/or mucus in the stool, diarrhoea, and frequent defecation of small amounts of faeces. Chronic colitis may result in weight loss. Dogs with colitis can be managed through diet or a combination of diet and medication.
The more common causes of colitis include:
- Bacterial, viral, fungal or parasitic infections
- Eating non-food items such as grass, plastic or fabric.
- Food allergy
Reducing the risk of your dog getting colitis
Try to keep an eye on your dog and he eats, and keep rubbish and other ingestible materials out of reach and securely away from your dog.
Your vet may prescribe medication. He or she may also recommend a special diet and/or dietary supplement that provide nutritional support for your dog.
Effective treatment for your dog
Depending on the severity and type of problem, your dog’s treatment can involve either short-term or ongoing dietary management or medical management. If additional diagnostic tests are needed your vet may recommend laboratory analyses, x-rays, or endoscopy - which involves inserting a tube with a small video camera into your dog’s digestive tract. This can help visualise the problem. In some cases a sample of gut may need be taken or abdominal surgery may be required.
Stress diarrhoea in pets is a common physical response to stress or anxiety. Examples of stressful situations that can trigger gastrointestinal upset include adoption, boarding, separation from the owner, changes in the household or environment, and introduction of a new pet or family member.
Reducing the risk of your dog getting stress diarrhoea
If possible, ease your dog through transitions and let him acclimatise to new experiences gradually. Some vets may recommend a pro-biotic supplement, which supplies beneficial bacteria to restore balance in the intestine. It can also be used when a stressful situation is anticipated to help keep your dog’s digestive tract in check.
When pets are anxious or upset, they can experience acute, short-term diarrhoea. Again, a pro-biotic supplement can be used to calm the digestive tract and restore the balance of microflora in the intestine that is disrupted by gastrointestinal upset.
If your dog is straining to defecate or has hard stools, he’s possibly constipated. There are many reasons why this can happen – dehydration, a lack of fibre, or an enlarged prostate may play a role. However constipation can also indicate more serious problems such as a growth, a tumour or neurological problems. If you think your dog is constipated make sure he has enough fibre or roughage in his diet, is drinking plenty of water and is getting enough exercise.
Good quality complete diets are formulated to provide balanced nutrition with adequate levels of fibre in the diet. The value of fibre to help minimize constipation is well known. Fibre absorbs water and lends bulk to the intestinal contents. This stimulates the movement of the intestinal tract and normalizes passage time through the bowel. Fibre sources also contribute to faecal consistency. Excessive dietary fibre is associated with adverse effects such as loose stools, flatulence (gas) and increased stool volume. Sources of dietary fibre often found in complete manufactured dog foods include beet pulp, the bran of oats, rice and wheat.
If your dog has sudden and/or persistent constipation you should seek veterinary advice. Treatment may be required and will depend on the cause, and may include medication, a stool softener or a high fibre diet.