What Causes Dark Green Stool In Dogs. Although less common iron toxicity in your dogs system can also result in dark stools. This is a condition known as Melena and is potentially serious. There are also some rodenticides that have a greenish or greenish-blue coloring and can cause a dogs poop to turn green when eaten. Dark green poop can be related to eating grass or other foods with a lot of green color or could be caused by an upset stomach or intestinal parasites.
Once a dog has giardia it is a carrier for life. Giardia forms a hard shell-like cyst around itself and it lives in a dogs intestines for a long time. The black coloration might actually be different from what you think its a condition called melena and it is caused by digested blood thats made its way into the dogs stool. Many human medications especially aspirin can cause stomach ulcers in dogs. Hepatic liver disease the use of non-steroidal anti-inflammatory drugs and neoplasia which is the abnormal growth of cells. This is a condition known as Melena and is potentially serious.
The most common cause of dark stool in dogs is the presence of digested blood in the stool.
This is called melena Melena in dogs can occur with any condition that affects the stomach or upper part of the intestine including inflammation ulcers and cancer. Green poop discoloration could also be from eating too much grass and some dental treats like the OraVet chews and Greenies can also give a greenish discoloration to a dogs stools. Some owners are not aware that dark stool can actually mean the presence of blood. Consult your veterinarian if your dog is passing black smelly stools on a regular basis. If your dog is acting normal otherwise you can try feeding a bland easily digestible diet of plain boiled chicken and rice for the next few days to see if his stool returns to normal. The causes of melena vary widely and can mean anything from exposure to toxins or a foreign body in the gastrointestinal system to pancreatitis and kidney failure.