Diarrhoea is one of the most common digestive problems in dogs. But in puppies, in particular, it should set alarm bells ringing and must be treated by a vet as quickly as possible. New-born puppies are almost always infected with round- worms from the mother. The mother should therefore be wormed before the birth, and the puppies shortly after birth - when they are about 2 weeks old. Giardia (single-celled parasites) are another frequent cause of severe diarrhoea in young dogs and must be treated by a vet.
In adult dogs it is generally the wrong food or infections that trigger the digestive disorder. Intolerances, autoimmune diseases, infections of the pancreas and many other illnesses can also cause diarrhoea, however.