If you notice your dog is bruising easily or bleeding with no obvious cause, a trip to the veterinarian is in order. Your pet may have one of several types of bleeding disorders that can affect canines. These disorders occur when the blood does not clot normally, in turn causing the dog to bleed abnormally or excessively after any minor injury or cut.

There are a number of warning signs that indicate your dog may have a blood disorder. Be watchful for any bleeding or bruises that have no obvious cause, frequent nosebleeds and blood in the animal's urine or feces. Also, the gums may be pale, and there may be tiny pinpoint-sized red spots on the gums or the whites of the eyes. If your dog becomes tired easily, he also may have anemia, which results from a reduced number of oxygen-carrying red blood cells.

Many of the signs above will be obvious to the pet's owner. However, bleeding also can occur internally, resulting in pools of blood in the dog's abdominal cavity, abdomen or chest which may cause the abdomen to become distended or interfere with breathing. In rare cases, the dog can bleed into the brain or spinal cord, causing seizures, fainting and even paralysis. If you suspect your pet has any type of bleeding problem, then it's time for a trip to the veterinarian.

Among the many types of disorders that can affect your dog's blood are:

Hemophilia. A genetic abnormality means the dog's blood is deficient in one of several types of clotting factors, specifically factors VIII or IX. As a result, the animal's blood cannot clot.

Von Willebrand's Disease. Again, the dog is missing von Willebrand factor, so the blood cannot clot. This disorder is also genetically inherited.

Thrombocytopenia. In this condition there are too few platelets, which are the blood cells that clump together to stop bleeding and basically "plug the hole" when a blood vessel is torn. Without enough platelets, the blood cannot clot effectively and prevent bleeding after an injury.

Thrombocytopathy. Here there are enough platelets, but they are chemically deficient and not sticky enough. Because of this, they are not able to clump together and plug a torn blood vessel.

Soluble Coagulation Factors. These factors are found in the plasma, which is the liquid portion of the blood. Normally, when blood vessels are torn they release chemicals that tell the plasma to produce fibrin. Fibrin is a substance that helps anchor the clumping platelets on top of the tear in the blood vessel. When these coagulation factors are reduced in the blood, the platelets are swept away from the hole they are trying to repair, again causing bleeding.

Bleeding disorders in dogs are diagnosed through a complete physical exam and a number of laboratory blood tests. Whenever possible, treatment should be aimed at the specific underlying disorder.

Dogs that are anemic (that have too few red blood cells) or who have lost a lot of blood may be given a transfusion of either red blood cells or whole blood (red blood cells plus plasma). In some cases the underlying cause must also be treated. Many cases of thrombocytopenia are caused by an infection or other type of illness, which must be treated with antibiotics or corticosteroids before the thrombocytopenia can be resolved.