What could it be and when to worry


by Dr. Chantal Moreton, BVSc


Diarrhoea is defined in the dictionary as “excessive and frequent evacuation of watery faeces” but not all episodes are the same and can mean many different things.


Sometimes it can be a one-off episode or on-going, happen intermittently, have blood in it, be dark in colour, be more pale in colour, be green, excessively smelly, have interesting objects in it, have worms in it!  Your pet may be off colour, straining and not wanting to eat or acting completely normally otherwise. So what does it all mean and when do you need to worry about it?


Diarrhoea can be caused by many different things but generally falls into 5 categories:

  1. bacterial or viral infection – the typical tummy bug – contracted from another animal or from eating something they shouldn't – food poisoning
  2. parasites e.g. round worms, giardia, coccidia
  3. inflammatory bowel disease (IBD) or colitis – sometimes due to a particular food allergy or can be stress induced
  4. systemic disease i.e. disorders of the pancreas/liver/intestines
  5. cancer


Image source wikimedia commons



With any bout of diarrhoea the first thing to remember is personal hygiene – wear gloves when handling any faeces and wash your hands. Bacterial infections or parasite burdens can sometimes pass to humans – don't take any risks. Be aware of other pets in the household as well – try to isolate the affected pet.


Sometimes, a bout of diarrhoea will clear up on its own and no medical consultation/therapy is required. The most important thing is to keep up the pet's fluid intake (preferably water) and you can always feed a bland diet e.g boiled chicken and rice to a) encourage food intake and b) it is soothing on the gut.


If however, your pet's diarrhoea has been going on for some time or they are not eating, looking generally miserable or have other symptoms e.g. vomiting then they should definitely be seen by your veterinarian. Diarrhoea can lead to dehydration very quickly and some conditions can be life threatening if not caught early. The disease most commonly thought of is Parvovirus in dogs – a viral disease that is very contagious and has a high mortality rate especially in young dogs – vaccination from an early age has helped to reduce the frequency of this nasty disease.


The veterinarian will examine your pet's vital signs and ascertain the best course of treatment – sometimes as simple as a course of antibiotics, parasite control and bland food but can involve i/v fluid therapy, blood tests and a prolonged stay in hospital.


Prevention is the key for most cases of diarrhoea – ensure your pets are vaccinated, wormed regularly and fed an appropriate diet. Keep them away from old rubbish bins and rotting things on your walk. Stagnant water can also be a source of infection – e.g. giardia.


Sometimes, your pet's diarrhoea will not resolve after the first trip to the veterinarian. In this case, the veterinarian will often request a sample of the faeces to send away for laboratory testing – this will help rule out bacterial/viral/parasitic conditions. If the faeces are negative for these then further investigation will be needed. This can involve blood tests to check for vital organ health, food trials to check for food allergies/intolerance or sometimes biopsies of the intestines.


Diarrhoea is an unpleasant condition for both our pets and us but is something we can deal with – you don't have to suffer. If you have any doubts or worries, don't hesitate to ring the clinic and discuss your pet's symptoms with us.


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