Health

Like most large breed dogs the Leonberger breed has some health risks. Reputable breeders work hard to reduce the incidence of health issues in their puppies.  All reputable breeders will certify their dogs for hip and elbow dysplasia. This is done by taking a set of x-rays and submitting the x-rays to the Orthopedic Foundation for Animals (OFA) for certifications.  OFA gives three passing ratings for hips – excellent, good and fair.  Most breeders try not to breed two OFA fair rated dogs together.

Reputable breeders of Leonbergers will test their dogs in the following areas.

  • Displasia in both hips and Elbows
  • Eyes for cataracts or any genetic conditions which may affect sight
  • LEMP (see below for description)
  • LPN 1 and LPN2 (see below for description)

If you are on a quest for a puppy Leo to join your family, it is well advised to speak to any potential breeder about testing for these issues to begin your journey with the healthiest possible pup.

Cancer is also a problem that needs careful consideration.  Owners can help keep their dogs healthy by not using too many environmental chemicals and by providing the best quality nutrition to their dogs.

Some of the common health concerns are listed below:

Hip Dysplasia: Hip dysplasia can occur in many large breed dogs including the Leonberger.  Hip dysplasia is when the ball and socket of the hip joint do not fit snuggly and this often results in arthritic changes.  There is a wide range of severity of hip dysplasia, with some dogs being mildly affected and others being very severely affected.  All dogs are born with normal hips and hence hip dysplasia is a degenerative disease and progresses as the puppy grows and ages.  Over nutrition and a heavy body weight has been shown to enhance the severity of hip dysplasia.  Puppies should be fed a limited diet of high quality food that promotes slow and steady growth.  Puppies should also be allowed to have a lot of free time outside where they can develop their muscles.  All Leonbergers that are bred should have OFA passing hips at 24 months old.

Osteochondritis Dessicans (OCD): OCD is a condition where an area of cartilage dies and falls into the associated joint. OCD can happen spontaneously or can be the result of injury.  OCD is often associated with the shoulder joints and less common with the hock joints.  The cartilage flap can sometimes become mobile in the joint and are often called a ‘joint mouse’.  The cartilage flap or joint mouse causes significant discomfort and swelling and often the dog will become quite lame.  Surgery is carried out to remove the cartilage flap and typically this will resolve the issue and reduce the lameness.

Cancer: There are several different types of cancers that are can affect the Leonberger.  Bone cancer or osteosarcoma has a relatively high incidence in the Leonberger and the prognosis is typically poor.  Another cancer that is has a high frequency is hermangoisarcoma which can affect several of the organs. Hemangiosarcoma is a cancer of the lining of some blood vessels. It occurs most commonly in the spleen, liver and in the heart.  Breeders are always striving to improve the longevity of their dogs and reduce the incidence of these cancers.

“Pano” Eosinophilic Panosteitis: is a generalized inflammation of the long bones that is commonly referred to as growing pains.  Pano can be readily diagnosed with an x-ray of the forelimbs.  Typically a young Leonberger suddenly develops a painful lameness with no known history of trauma.  The lameness often shifts from one limb to another and often occurs between the ages of 8 and 12 months with males being more affected than females.  Anti-inflammatory drugs may be prescribed, and attempts to slow the rate of growth of the puppy are often recommended.  Pano can be reoccurring as the puppy continues to grow but typically the severity lessons as the puppy ages.  Pano is self-limiting and does not cause any lasting damage to the bones.

Eye Problems: Cataracts are an opacity of the lens which may occur in a number of different locations within the lens. Cataracts can be of varying sizes, from a number of different causes (hereditary and not), and may occur early or late in life. While some cataracts can cause blindness others may have minimal or no affect on vision.  All Leonbergers bred should have no evidence of inherited eye disease via a certified ophthalmologist.

Bloat: Also known as gastric dilation, bloat can occur in any breed and is known to occur with some frequency in the Leonberger. In deep-chested breeds the stomach can fill with gas and twist, trapping the gas inside. This is a life-threatening event and immediate veterinary care is needed.  Bloat is a true medical emergency.  Signs of bloat are trying to vomit without producing anything, foaming at the mouth, severe discomfort with the inability to lie down, and roaching or arching of the back.  As a preventative measure, Leos should be fed at least twice a day and should not be vigorously exercised or stressed for at least one hour before and after feeding.

Inherited Polyneuropathy (LPN) Leonberger Polyneuropathy  is a collective term for several clinically similar neuromuscular diseases. The dog suffers from slowly worsening exercise intolerance and may develop gait abnormalities, such as an exaggerated “hitched” step, especially in the hind limbs. There is often wasting of the hind limb muscles. Additionally, these dogs may have noisy breathing, a change in their bark, or even difficulty breathing due to involvement of the larynx and laryngeal folds in the throat. Eventually the disease may progress to the point where the dog cannot support its own weight. Biopsies of nerve from affected dogs show degradation of the nerve fibers and loss of myelin, the insulating material that normally helps speed messages along nerves. Muscle biopsies show atrophy resulting from nerve loss. Leonberger polyneuropathy is caused by at least two independent gene mutations. Genetic tests are available for LPN Type 1 (LPN1) and LPN Type 2 (LPN2) and all breeding Leonberger should have their genetic information known.

Leukoencephalomyelopathy (LEMP) stands for Leukoencephalomyelopathy. LEMP is part of a group of neurological illnesses known as leukodystrophy. A genetic test is available for LEMP and all breeding Leonberger should have their genetic information known.

Perianal Fistulas: Perianal fistulas are chronic deep, draining, sacs located around the anus. Perianal fistulas are very difficult to heal and are thought of as an autoimmune related disease, and can be quite painful.  The cause of perianal fistulas is not clear at this time but this ailment is known to occur in the Leonberger breed.