Loose stools in dogs can occur for a number of reasons. While often caused by small disturbances in the digestive system, loose stools---or diarrhoea---can also be an indication of a serious medical condition. While mild cases of diarrhoea in dogs are usually no cause for alarm, they can also be representative of an intestinal disease, the most common ones being coccidiosis and giardiasis. As most dogs will experience loose stools at some point (or points) in their lives, it is up to the dog owner to diagnose if the problem warrants veterinary assistance.
Diarrhoea in dogs is a condition that involves the passing of an abnormal amount of liquid or loose stools. There are many causes, which range from minor to extremely serious. These include an abrupt change in diet, intolerance to milk, allergies to dog foods, eating from the garbage, an object stuck in the intestinal tract, bacterial and viral infections, and worms and parasites.
When to Seek Medical Attention
Mild cases of loose stools usually resolve in 1 to 2 days. If the problem lasts longer than this, it is a good idea to bring the dog in for a consultation with a veterinarian. However, it is also important to judge the dog's comfort level. If the dog is functioning---or in the case of puppies, growing---normally, and does not seem to be in any pain, there may be no need to subjugate the dog to a medical exam or medical testing. In contrast, if the diarrhoea contains mucus or blood, or is accompanied by gas, vomiting, lethargy or appetite loss, a serious medical condition may be present.
Loose stools in dogs can only be properly diagnosed by veterinarians. The first step often involves the examination of a stool sample. Veterinarians look for indications of intestinal parasites and observe fecal smears for signs of bacteria that cause intestinal problems. Blood chemistry panels and blood cell counts are also tests performed in the preliminary stages and help rule out systemic causes of loose stools like kidney of liver problems.
One of the most common causes of diarrhoea or loose stools in dogs is the disease coccidiosis. It is caused by tiny protozoan (coccidias) that reproduce in the intestinal tracts of many pets and animals, especially dogs. The disease principally affects younger dogs, as dogs grow immune to the coccidias with age. The protozoan may exist in a dog's intestine for a lifetime and show no ill effects.
Giardiasis, like coccidiosis, is also cause by small protozoan (giardia). Dogs as well as many other animals can contract giardiasis by eating infected food or drinking contaminated water. When the protozoa reach the intestines, they multiply and block absorption, which results in loose stools and diarrhoea.