Sporting Gun's vet gives a concerned gundog owner some advice
Q: “Can you explain to me why my gundog gets a stomach upset? What causes diarrhoea in dogs and how can I stop my gundog getting it?
Diarrhoea in dogs – the symptoms and the causes
Diarrhoea is defined as increased water content of faeces, leading to changes in frequency of passing, fluidity or volume of faeces. This occurs because of one or more of:
• Altered motility of the bowel
• Reduced absorption of water
• Increased secretion of water
• Altered permeability of the bowel lining
There are numerous ways to separate different types of diarrhoea into groups, which can be useful for diagnostic purposes.
Is it the upper or lower bowel?
Generally when the upper bowel, or small intestine, is affected, you will see:
• Mild increase in frequency of passing faeces
• Large volume of faeces
• Colour changes, including ‘changed’ blood
• Weight loss (as absorption of nutrients is affected)
When the lower bowel, or large intestine is involved, you expect:
• Increased frequency to more than three times daily.
• Mucus (jelly-like or shiny covering)
• Fresh red blood (not black)
• Urgency and straining (so more ‘accidents’)
• No loss of weight
Causes of diarrhoea in dogs
The list of causes of diarrhoea in dogs is nearly endless. The dog’s recent history can be crucial. For example, has it been scavenging? Has there been any change of diet? Has the dog been dewormed effectively? Is there the possibility of another disease? Are in-contact animals (or humans) affected?
Perhaps one of the most important aspects is whether the problem is acute (that is to say a sudden onset, continuous and of less than a week’s duration) or chronic (present for more than two weeks and comes and goes).
The causes can be broken down broadly into:
• Dietary indiscretion
• Ingestion of toxins
• Bacterial infections (campylobacter, salmonella, E. coli)
• Viral infections (parvovirus, coronavirus)
• Parasitic infections (roundworms, hookworms, whipworms, giardia)
• Food allergy
• Irritable bowel syndrome
• Other disease processes
• Foreign body (though generally they stop passing faeces)
• Abdominal catastrophe (twisted bowel)
Treatment may involve faecal culture to look for infectious agents, withholding food for 24 hours (water little and often), the use of gut protectants and judicious use of motility modifiers, such as loperamide. It is also essential to worm regularly.
I have never been too sure exactly when acute diarrhoea becomes chronic. This is another problem, so requires another list:
• Other diseases (such as pancreatic insufficiency, heart issues, Addison’s disease)
• More infections (Yes, as previous)
• Dietary intolerance
• A lack of antibiotics
• Tumours (especially lymphoma and intestinal cancers)
• Irritable bowel syndrome (again)
• Foreign body
All of the aforementioned should highlight how complicated diarrhoea can be.
What a vet should investigate
• Faecal culture (a must in severe cases)
• Pancreatic tests (for inflammation or insufficiency)
• Blood cell count (evidence of infection, parasites)
• Biochemistry testing (liver, kidney, Addison’s disease)
• Urine sampling (evidence of organ disease, protein loss)
• Serum folate and cobalamin (B12) levels (distinguish maldigestion and malabsorption)
• Intestinal biopsies (a last resort)
Which dog breeds are more prone to diarrhoea?
Some breeds are prone to specific problems that cause diarrhoea. These include: gluten-sensitive enteropathy in Irish setters; familial protein-losing enteropathy of soft wheaten terriers; and granulomatous colitis of boxers, French bulldogs and bulldogs (which I include just in case you were thinking of straying).