Von Willebrand's Disease (VWD) - Von Willebrand's Disease is a common inherited bleeding disorder.

Clotting is a complex mechanism. In addition to platelets, clot formation is the result of a long chain of chemical reactions carried out by individual molecules called 'clotting factors.' Each factor is numbered such that factor I leads to a reaction with factor II forming a new substance. This then reacts with factor III and so on to factor XII.

In Von Willebrand's Disease, the dog is missing a substance, which helps the platelets form clots and stabilizes Factor VIII in the clotting process. This substance is called 'Von Willebrand's factor.' Because of the deficient clotting of blood, dogs with Von Willebrand's disease have excessive bleeding upon injury. This would be similar to hemophilia in humans.

Certain breeds have a higher incidence of VWD than others. German Shepherds, Doberman Pinschers, Shetland Sheepdogs, Chesapeake Bay Retrievers, German Shorthaired Pointers, Golden Retrievers, Standard Poodles, and Scottish Terriers all have a higher than normal incidence, showing that it can be inherited.

What are the symptoms?  Excessive bleeding is the main symptom. Bleeding generally occurs after a wound or surgery. In these cases, the blood simply does not clot in the normal time, and bleeding is extensive. Dog's with Von Willebrand's disease may also develop nosebleeds, or bleeding from the gums. Bleeding may also occur in the stomach or intestine in which case the stool may either have blood in it, or be black and tarry. Some dogs will have blood in their urine. Bleeding into the joints also occurs, which can cause symptoms similar to those of arthritis.

The diagnosis of Von Willebrand's is made through a test, which checks for the level of Von Willebrand's factor in the blood.

Hypothyroidism - Low circulating thyroid level, which can result in skin, coat and weight abnormalities, behavior changes, and fertility problems.  The thyroid gland is located next to the dog's trachea and produces two primary forms of thyroid hormone: thyroxine and triiodothyronine.  Another hormone, thyroid-stimulating hormone (TSH), is secreted by the pituitary gland and regulates the thyroid gland's production and secretion of thyroid hormone.  The major function of thyroid hormone is to regulate cellular metabolism.  As a result, a lack of this hormone affects many body systems.  Hypothyroidism is considered to be the most common hormonal disorder in the domestic dog.  It is characterized by inadequate secretion of thyroid hormone from the thyroid gland, low levels of thyroid hormone in the blood, and the resultant clinical effects.  The onset of clinical signs of hypothyroidism occur after the dog is an adult, typically between 4 and 8 years of age.

Cause: Hypothyroidism may have several underlying causes.  It may be a result of an immune-mediated problem (lymphocytic thyroiditis), atrophy of the gland, decreased levels of TSH, or the presence of a cancerous growth in either gland.

Although the onset of clinical signs is variable, hypothyroidism most commonly develops in middle-aged dogs between the ages of 4 to 10 years. The disorder usually affects mid to large size breeds of dogs, and is rare in toy and miniature breeds of dogs. Breeds that appear to be predisposed to developing the condition include the Golden Retriever, Doberman Pinscher, Irish Setter, Miniature Schnauzer, Dachshund, Cocker Spaniel, and Airedale Terrier. German Shepherds and mixed breeds appear to be at a reduced risk of contracting the disease. There does not appear to be a sex predilection but spayed females appear to develop it more often than intact females.

Other medical problems can include:

Osteochondrosis - Osteochondrosis is a painful malformation of the joint cartilage which can affect puppies of rapidly growing large breeds.  Osteochondrosis dissecans occurs when the affected area is further traumatized and a cartilage "flap" develops, resulting in acute pain.

In all animals, osteochondrosis can affect many different joints, but in the dog, the most common sites of disease are the shoulder, elbow, stifle or knee joint, and tarsus or hock. Generally, osteochondrosis occurs in young, large to giant breeds, although it is also seen in mixed breeds. The most commonly affected breeds include the German shepherd, golden and Labrador retriever, Rottweiler, Great Dane, Bernese mountain dog, and Saint Bernard.

Prevention
Prevention generally includes avoiding calorie-dense diets in large to giant breed dogs. Puppies should be fed adult diets or giant breed growth formulations, and vitamin over-supplementation should be avoided. Maintaining a lean body condition also seems to decrease the risk of osteochondrosis. 

Liver Shunt - Liver shunts are abnormal blood vessels which cause the blood supply to bypass the liver.  They are usually present at birth. Liver shunts are a congenital problem in some dogs. During gestation the placenta delivers blood with food and oxygen from the mother through the umbilical vein. This means that in the fetus, circulation is the reverse of circulation after birth, because the fetus' veins have the oxygenated blood and arteries return unoxygentated blood to the heart. In order to make this work, there is a shunt from the liver venous circulation to the arterial circulation. At birth, the pressure within the circulatory system changes as respiration occurs and this shuts the shunt, which eventually disappears. If this reverse in circulation doesn't happen for some reason, the liver is deprived of a blood supply and doesn't develop properly after birth. Many puppies can live with the small functioning portion of the liver for some time but eventually have problems and usually die if the situation is uncorrected. It is possible to surgically close the shunt and the surgery works well. I can remember hearing of one sheltie that was 6 years of age (or possibly older) before a congenital liver shunt was recognized, so some dogs can live a long time with this problem.
 

Hip Dysplasia - affects the hip joints - one or both (usually both) become loose, partially dislocated and become subject to severe arthritic changes.  Symptoms can vary from no outward signs to total inability to function.

Breeds with High Incidence               

Rottweiler                                        

German Shepherd Dog 

Bloodhound

St. Bernard

Kuvasz

Newfoundland

Bullmastiff

Great Dane

Bernese Mountain Dog

Golden Retriever

Labrador Retriever

Chow Chow

Welsh Springer Spaniel

Breeds with Low Incidence

Borzoi

Saluki

Greyhound

Whippet

Afghan Hound

Siberian Husky

Belgian Sheepdog

Irish Wolfhound

Most small breeds (<35 Ibs)

Elbow dysplasia - a malformation of the elbow joint, usually affecting both elbows, leading to pain and lameness of varying degrees.  As in hip dysplasia, severe arthritic changes usually develop.  Affected dogs are frequently lame or have an abnormal gait. The gait is often characterized by excessive paddling or flipping of the front feet. The animal may either hold the elbows out or tucked in and often stands with the feet rotated outward. Many sit or lie down much of the time, or play for shorter periods of time than other dogs of comparable age. They are often described as quiet or even lazy. Frequently, they are stiff when rising and tire easily. Exercise typically makes the lameness worse. In dogs with bilateral elbow dysplasia, the lameness may seem intermittent or shift from one front leg to the other. When both front legs hurt, dogs do not limp constantly. Rather, they shift weight off their elbows by altering their gait and stance. These dogs will only "limp" when one elbow is more painful than the other. On examination, manipulation of the elbow is often resisted. Swelling and crepitus (grating) may be palpated. The swelling may be worse after exercise. In some cases, the joint will be thickened. Muscle atrophy may also be present.

Megaesophagus - Weakness of the esophagus, can be congenital or develop secondary to other diseases.  Regurgitation (not vomiting) is usually the first symptom noticed.

Progressive Retinal Atrophy - A hereditary, blinding disease of the retina of the eye.  PRA is an inherited retinal degeneration that occurs in two forms, central and generalized, the latter being the more common form.  The generalized form affects the photoreceptor area of the retina.  One indication of this form of PRA is the onset of night blindness, which will eventually progress to loss of day vision and then total blindness.  The central form (CPRA) affects the deepest layer of the retina which lies just below the photoreceptor layer.  There is no effective treatment for either form of PRA.

Fibrocartilaginous Embolic Myelopathy (FCE) - Pieces of cartilage-like material lodge in blood vessels supplying the spinal cord, causing mild to severe forms of paralysis.  Most prevalent in large and giant breed dogs of 3-5 years, but can happen at any age, even to puppies.

Seizures - Seizures can be epileptic in nature or non-epileptic (organic causes, disease, trauma, toxicities).

More resources:  the Canine Epilepsy Network, and the EPI Support Group.

For additional canine health information: The Canine Health Foundation

Remember, even if your wolfhound seems to be in good health, a Yearly Health Check is most important.  When you choose your vet be sure to find out what services are offered (24 hour emergency coverage, what surgeries are or are not performed, to whom and where does the veterinarian refer, etc).

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