While most diseases in dogs are seen equally in all sizes and breeds, there are some diseases that are seen almost exclusively in larger breed dogs. The following list contains some of the most common illnesses that occur in large breed dogs. Keep an eye out for these potential diseases if your dog is a large breed.
1. Bone Cancer
Large breed dogs are by far the most common sized dogs to get bone cancer. Typically, this is a special type of cancer called Osteosarcoma. It is most often found in the limbs around the knee joint, the shoulder joint and the wrist joint. Typically, older dogs with this disease will develop firm swelling in the affected part of the limb and they will eventually limp from pain. The cancer eats away at the bone which means that these lesions can fracture or break easily. If you notice a swelling on any part of your dog’s limb or limping, it is best to have it checked out immediately. Radiographs (x-rays) are used to find the lesion and biopsies are often done to confirm cancer.
2. Bloat
This condition which commonly includes twisting of the stomach, is called Gastric Dilatation and Volvulus, or “GDV” for short. This occurs almost exclusively in deep chested, large breed dogs such as Great Danes, German Shepherds and similarly built breeds. However, it can theoretically happen in any breed or size of dog. Often times, it occurs after the dog has eaten a large meal and exercised. This is why it is important to not overfeed large breed dogs, encourage them to eat slowly to avoid swallowing excess air, and avoid exercise and play until digestion has finished. When the stomach fills with air, it may twist around causing extreme pain. When the stomach twists, it prevents the air from escaping and dogs may often attempt to retch and vomit unproductively as a reflex to their stomach bloating. The bacteria in the stomach continues to produce gas which worsens the issue. These dogs are extremely uncomfortable, painful, unable to eat and show signs of not acting like themselves. In advanced cases, their abdomens will become very distended as the gas continues to build up in the stomach. This is always an emergency and almost always requires emergency surgery as treatment. If your dog bloats, he should be seen immediately for treatment as the stomach wall will begin to necrose and die from lack of blood flow. In addition, the stomach could rupture and “pop” if the pressure builds too much causing a deadly infection in the abdomen. There is a preventative surgery called a Gastropexy that can be done to ensure that your dog does not get this life threatening condition in the future.
3. Hypothyrodism
While all dogs can have low thyroid hormone levels, this disease most commonly affects large breed dogs such as Dobermans, Weimaraners and Labrador Retrievers. Middle aged to older dogs may experience significant weight gain despite a normal or low appetite, a decrease in energy and playfulness as well as hair loss and skin changes. A simple blood test can be performed to tell if your dog’s thyroid hormone level is low. If it is, a daily medication can supplement the hormone and return your dog’s weight, energy and hair coat back to normal.
4. Lymphoma
This type of cancer affects the Lymphocytes, a type of white blood cell. Most commonly affecting Golden Retrievers and Boxers, dogs with Lymphoma may act perfectly normal for a long time. Often times, the first sign of illness is swollen or enlarged lymph nodes under the chin and neck, near the shoulder, behind the knee or in the inner groin area. If you notice any abnormal lumps or bumps, especially in these areas or any that are growing larger, it is a good idea to have the mass biopsied. Lymphoma can also affect other organ systems such as the eyes, GI tract and skin. Some types of Lymphoma are curable with chemotherapy if caught early. However, this cancer is fatal if left untreated.
5. Splenic Mass
Large breed dogs are more at risk for tumors and masses on the spleen. Golden Retrievers are the most commonly affected breed, although it can happen in many other breeds. Often times these masses are cancerous and may spread to other organs in the body such as the lungs if not caught early. Sometimes, these masses are not malignant cancer and only affect the spleen. In either case, these tumors may rupture and cause massive, life-threatening internal bleeding. If this happens, often times dogs will need an emergency, lifesaving surgery called a splenectomy. This procedure removes the spleen, stopping the bleeding and preventing further blood loss. If a mass is found on the spleen before it ruptures, it may be a good idea to go ahead and have it removed before a critical bleeding episode occurs. The tumors don’t usually show any obvious outward signs until a massive internal bleed happens, so it’s a good idea to have screening radiographs (x-rays) or ultrasound done yearly on older pets to catch and fix this problem before it becomes life-threatening.