Glossary

EIC has been tested for a while in labradors. It is an autosomal recessive genetic disorder causing affected dogs to experience a collapse during or after extreme exercise. Typically an affected dog starts to manifest the disorder around five months to three years of age. With vigorous exercise lasting 5-20 minutes, a loss of control becomes apparent in the hind limbs. Starting as a wobbly gait, the loss of control progresses to collapse, and sometimes dogs may seem confused. Occasional deaths have been reported. Not all types of exercise can induce an attack: the dog generally would be actively running or excited for an extended period of time.

Because EIC is a recessive disorder, a dog must have two copies of the muted gene in order for the disease to manifest. This means a dog can have one copy of the mutation and not experience EIC, but would be considered a carrier. Dogs with EIC can still lead full lives. However, its important to be familiar with what types of activities trigger an episode

PRA terms a group of inherited eye diseases that cause loss of vision due to degeneration of the retina. Testing for PRA has been available since the mid-1990s. Its known in each breed of dog, including mixed breeds.

In PRA the rod cells in the retina die in both eyes simultaneously and is non-painful. Because the rod cells in the retina die, and rod cells are responsible for vision in low light, vision in dim light (such as night) is first affected. The disease causes gradual blindness, but eventuates into complete blindness months or years later. Towards the end of the disease the affected eyes develop cataracts.

Although PRA in most affected dogs cannot be cured, in the opinion of many modern veterinary ophthalmologists, it is no longer a hopeless disease that always leads to complete blindness. New insight into the mechanisms of retinal damage from oxidative stress has resulted in much more hope for prolonging vision of affected dogs.

HNPK is an inherited skin disorder that affects labradors. It is characterized by the development of dry skin and crusting on the nose, that can lead to cracked skin, fissures, and chronic inflammation of the skin on the nose. Generally parakeratosis is a benign skin condition. It is not physically contagious.

Affected dogs begin showing clinical signs around six to twelve months of age. They develop dry, rough crusts on the tip of the nose. In extreme cases, the dog’s nose will crack causing severe discomfort. Lesions can occur on the area around the nose. The noses of these affected dogs are prone to bacterial infections and can lose pigment over time. This disorder may be treated with veterinary consultation and topical therapy.

DM is a progressive ‘degenerative’ neurological disease of the spinal cord and nerves, predominately seen in german shepherds over six years of age, but found a handful of other breeds aswell, including occasionally in labradors. The human equivalent would be motor neuron disease. Degradation of the myelin sheath causes disruption to signals and messages from the brain reaching the intended destination, such as movement signals getting to the legs. Initial symptoms are loss of coordination in the hind limbs, progressing to loss of hind leg use, rendering the dog immobile and causing atrophy (loss of muscle), incontinence, and eventually difficulty breathing and failure of major organs as the nerves further up the spinal cord become affected. The nerve disease renders the dog paraplegic, and is not painful. There is no cure for DM, however, there is a medication regime that helps slow down the progression of the disease.

This disease is normally seen around middle age, and in general diagnosis can only be confirmed at post mortem examination. Signs are due to the immune-mediated destruction of a part of the nerves in the spinal cord, leading to loss of these nerve fibres. The first sign is knuckling of the hind feet, and hind limb ataxia. Once the spinal cord damage progresses past this initial stage (termed proprioceptive deficits), the effectiveness (if any) of treatment is much diminished. Hence early diagnosis is vital. Following this initial stage, hind limb reflexes are affected, then weakness in the hind limbs develops, progressing to total paralysis. Once a dog shows these signs it will almost always respond poorly to therapy. Eventually destruction progresses from the middle of the spinal cord to the upper cord and brain stem, leading to forelimb weakness and eventually interference with the muscles of breathing, causing death. Most dogs are euthanised for humane reasons before this happens.

A new mutation causing dilution of coat colour.