Centronuclear Myopathy

Centronuclear Myopathy is an inherited progressive muscle disease affecting dogs. Though the severity of symptoms is variable, affected dogs typically present between 6 weeks to 7 months of age with exercise intolerance, awkward gait and difficulty eating. As the disease progresses, symptoms also include generalized muscle Atrophy, downward flexion of the head and neck, low muscle tone and more frequent episodes of collapse when exposed to cold temperatures. Progression of the disease tends to stabilize around one year of age and dogs typically have a normal life span, but affected dogs usually have life-long medical problems due to the underlying muscle disease.

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Cystinuria (Labrador Retriever Type) 

Cystinuria (Labrador retriever type) is an inherited disease affecting kidney function in dogs. The SLC3A1 gene codes for a protein that allows the kidneys to transport cystine and other amino acids from the urine. Normal kidneys reabsorb the Amino Acid cystine so that only small amounts pass into the urine, while dogs with mutations of both copies of the SLC3A1 gene fail to reabsorb cystine allowing large amounts to pass into the urine, hence the name cystinuria. Cystine can form crystals and/or stones in the urinary tract, which can block the ureters or Urethra and stop the normal flow of urine. Affected male dogs typically present with symptoms related to cysteine bladder stones at 6 to 14 months of age, however female dogs tend to develop symptoms later than males. Symptoms of disease include straining to urinate, frequent urination of small volumes or inability to urinate. In Labrador retrievers, males and females are equally affected with excess cysteine in the urine, but obstruction of urine flow is more common in males due to differences in anatomy and females tend to develop stones about a year later than males on average. Dogs with cystinuria often have recurrent inflammation of the urinary tract and if not treated, urinary stones can cause urinary tract infections, kidney failure and even death.

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Degenerative Myelopathy 

Degenerative Myelopathy is an inherited neurologic disorder caused by a Mutation of the SOD1 gene carried by many breeds of dog; though it is not clear for some breeds, such as the labradoodle, whether all dogs carrying two copies of the mutation will develop the disease. The variable presentation between breeds suggests that there are environmental or other genetic factors responsible for modifying disease expression. The average age of onset for dogs with degenerative myelopathy is approximately nine years of age. The disease affects the White Matter tissue of the spinal cord and is considered the canine equivalent to amyotrophic lateral sclerosis (Lou Gehrig’s disease) found in humans. Affected dogs usually present in adulthood with gradual muscle Atrophy and loss of coordination typically beginning in the hind limbs due to degeneration of the nerves. The condition is not typically painful for the dog, but will progress until the dog is no longer able to walk. The gait of dogs affected with degenerative myelopathy can be difficult to distinguish from the gait of dogs with hip dysplasia, arthritis of other joints of the hind limbs, or intervertebral disc disease. Late in the progression of disease, dogs may lose fecal and urinary continence and the forelimbs may be affected. Affected dogs may fully lose the ability to walk 6 months to 2 years after the onset of symptoms. Affected medium to large breed dogs, such as the labradoodle, can be difficult to manage and owners often elect euthanasia when their dog can no longer support weight in the hind limbs

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Elliptocytosis 

Canine elliptocytosis is a rare inherited blood disorder. Normal red blood cells are round in shape but red blood cells in affected dogs appear oval-shaped and can have serrated edges. An affected dog may present with mild Anemia and may be smaller than its littermates. Severe health complications have not been reported in affected dogs.

Exercise-Induced Collapse 

Exercise-Induced Collapse (EIC) is an inherited neuromuscular disorder affecting Labradoodles. EIC presents as exercise intolerance in apparently healthy dogs. Affected dogs are usually diagnosed before two years of age and appear normal during low to moderately strenuous activity. However, shortly after 5-20 minutes of strenuous exercise affected dogs will begin to walk with a wobbly, uncoordinated gait that often only affects the hind limbs. Dogs remain mentally alert and are not in pain during episodes of EIC. In some circumstances, the symptoms of EIC can progress to full body weakness with low muscle tone (flaccid paralysis), confusion, loss of consciousness, seizures and very rarely, death. The episodes typically last 5-10 minutes and most dogs will completely recover within 15-30 minutes.

GM2 Gangliosidosis (Poodle Type) 

GM2 gangliosidosis (poodle type) is an inherited Lysosomal Storage Disorder affecting dogs. Affected dogs have insufficient activity of the Enzyme hexosaminidase B, which is responsible for breaking down specific carbohydrates in the cells. As a result, there is an accumulation of a glycoprotein, GM2 ganglioside, in cells, especially cells of the brain and nervous system. Affected dogs typically present with symptoms of neurologic disease around 9 to 12 months of age. Symptoms include vision loss, difficulties walking, loss of balance, head tremors and vomiting. Once an affected dog begins to show signs of the disease, the disease progression is rapid and dogs usually die between the ages of 18 and 23 months

Hereditary Nasal Parakeratosis 

Hereditary nasal parakeratosis is an inherited disease affecting the nose of Labrador Retrievers. Beginning around 6 to 12 months of age, affected dogs develop dry, rough, gray to brown crusts and rarely, painful cracks on the tip of the nose. In some cases, lesions are also present on the haired area around the nose. The noses of affected dogs are prone to superficial bacterial infections and often become depigmented over time. Affected dogs are otherwise healthy. Symptoms often wax and wane in severity over the dog’s life. Though manageable, this disorder requires continuous topical therapy to prevent recurrence of excessive nasal crusting

Hyperuricosuria 

Hyperuricosuria is an inherited condition of the urinary system affecting several breeds of dog. The SLC2A9 gene codes for a protein that allows the kidneys to transport uric acid from the urine. Dogs with mutations in both copies of the SLC2A9 gene are predisposed to have elevated levels of uric acid in the urine, hence the name hyperuricosuria. Uric acid can form crystals and/or stones (uroliths) in the urinary tract. Dogs with hyperuricosuria most commonly present with symptoms of recurrent urinary tract inflammation, which include frequent urination, blood in the urine, and straining to urinate. They may also have loss of appetite, lethargy, weakness, vomiting and pain. Urinary stones in the bladder can cause urinary tract infections or more seriously, blockage of the Urethra. Both male and female dogs can be affected, but obstruction of urine flow is more common in males due to differences in anatomy. Although an x-ray can be used to exclude other types of stones, urate stones cannot typically be seen using x-rays and must be evaluated by ultrasound. Not all dogs with mutations in both copies of the SLC2A9 gene will have symptoms of disease, though they will have increased uric acid excretion in the urine.

Myotubular Myopathy 1 

Myotubular Myopathy is an inherited muscle disease known to affect dogs. Affected puppies are typically normal at birth, but between 7 and 19 weeks of age they present with muscle weakness especially in the hind limbs, decreased muscle mass, a hoarse bark and difficulty eating. Puppies are smaller than littermates, walk with a short, choppy gait and often fall over. The disease rapidly progresses from generalized muscle weakness and frequent episodes of collapse to a complete inability to stand or even raise their heads within 4 weeks of initial presentation. Dogs that are able to stand have an arched back and neck. While the disease is not painful, affected dogs are often euthanized between 3 and 6 months of age due to the rapid and severe progression of the disease

Narcolepsy (Labrador Retriever Type) 

Narcolepsy (Labrador retriever type) is an inherited disorder affecting dogs. Dogs with the inherited form of narcolepsy typically present between one to six months of age with an inability to stay awake for extended periods of time and episodes of collapse and sleep following positive stimulation such as play or food. Affected dogs fall asleep faster than normal dogs and appear sleepy more frequently. During episodes of collapse dogs have a sudden loss of muscle tone and appear uncontrollably sleepy but may or may not completely fall asleep. Symptoms do not progress after one year of age and affected dogs do not have other associated health problems.

Neonatal Encephalopathy with Seizures 

Neonatal Encephalopathy with Seizures is an inherited neurologic disease known to affect dogs. Affected puppies are smaller than littermates at birth, have difficulty nursing after a few days of life, and often die by 1 week of age. By 3 weeks of age, surviving puppies present with neurologic symptoms including muscle weakness, tremors, inability to walk, wide-based stance and frequent falling. The disease quickly progresses to severe seizures that become non-responsive to treatment. Affected dogs typically die or are euthanized by 7 weeks of age.

Osteochondrodysplasia 

Osteochondrodysplasia is an inherited Musculoskeletal disease affecting dogs. Affected dogs typically present at about 3 weeks of age with stunted growth. Puppies often walk differently than unaffected littermates and stand with their feet turned out and hind legs splayed. Their legs are short and bent with enlarged joints and clubbed feet. They also have flatted rib cages and under bites, which can affect their ability to nurse and breathe. While affected dogs can survive for many years with supportive care, they will develop arthritis and will likely have breathing difficulty due to their deformed ribcages.

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Progressive Retinal Atrophy, Cone-Rod Dystrophy 4 

Progressive retinal Atrophy, cone-Rod dystrophy 4 (PRA-crd4) is an inherited eye disease affecting dogs. PRA-crd4 occurs as a result of degeneration of both rod and cone type Photoreceptor Cells of the Retina, which are important for vision in dim and bright light, respectively. Affected dogs can show symptoms of vision loss or have signs of retinal disease on veterinary ophthalmologic exam by 3 years of age. However, age of onset varies significantly in PRA-crd4 affected dogs, and has been reported from 1 to 15 years of age. Mutations in the RPGRIP1 gene show Incomplete Penetrance, meaning that not all dogs inheriting two copies of the Mutation develop clinical disease. This suggests that other unknown genetic or environmental factors may play a role in modifying disease development and progression. Although progression tends to be relatively slow, most affected dogs (especially those with an early age of onset) will progress to complete blindness.

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Progressive Retinal Atrophy, Golden Retriever 2

Progressive retinal Atrophy, golden retriever 2 (GR-PRA2) is a late onset, inherited eye disease affecting dogs. Affected dogs begin showing clinical symptoms related to retinal degeneration at around 4 to 5 years of age on average, though age of onset can vary. Initial clinical signs of progressive retinal atrophy involve changes in reflectivity and appearance of a structure behind the Retina called the Tapetum that can be observed on a veterinary eye exam. Progression of the disease leads to thinning of the retinal blood vessels, signifying decreased blood flow to the retina. Affected dogs initially have vision loss in dim light (night blindness) and loss of peripheral vision, progressing to complete blindness in most affected dogs

 
Progressive Retinal Atrophy / PRCD

Progressive retinal Atrophy, progressive Rod-cone degeneration (PRA-prcd) is a late onset, inherited eye disease affecting Labradoodles. PRA-prcd occurs as a result of degeneration of both rod and cone type Photoreceptor Cells of the Retina, which are important for vision in dim and bright light, respectively. Evidence of retinal disease in affected dogs can first be seen on an Electroretinogram around 1.5 years of age for most breeds, but most affected dogs will not show signs of vision loss until 3 to 5 years of age or later. The rod type cells are affected first and affected dogs will initially have vision deficits in dim light (night blindness) and loss of peripheral vision. Over time affected dogs continue to lose night vision and begin to show visual deficits in bright light. Other signs of progressive retinal atrophy involve changes in reflectivity and appearance of a structure behind the retina called the Tapetum that can be observed on a veterinary eye exam. Although there is individual and breed variation in the age of onset and the rate of disease progression, the disease eventually progresses to complete blindness in most dogs. Other inherited disorders of the eye can appear similar to PRA-prcd. Genetic testing may help clarify if a dog is affected with PRA-prcd or another inherited condition of the eye
 

Pyruvate Kinase Deficiency (Labrador Retriever Type) 

Pyruvate kinase deficiency (Labrador retriever type) is an inherited metabolic disease affecting Labrador retrievers. Affected dogs have insufficient activity of the pyruvate kinase Enzyme which breaks down glycogen for energy. Deficiency of this enzyme results primarily in easily damaged red blood cells (hemolysis). Affected dogs typically present between 4 months and 2 year of age with pale gums from decreased numbers of red blood cells (Anemia) and lethargy or exercise intolerance. Clinical findings during a veterinary exam include severe anemia, hardening of the bones, and an enlarged spleen and liver. While dogs can live for several years with this disease, they typically die from severe anemia or liver failure by 5 years of age.

Retinal Dysplasia/Oculoskeletal Dysplasia 1

Retinal dysplasia/oculoskeletal dysplasia 1 is an inherited Collagen disorder affecting dogs. Dwarfism and eye abnormalities may be apparent as early as 4 to 6 weeks of age in affected puppies. The dwarfism is characterized by shortened forelimbs that become curved as the dog grows. In puppies, the top of the head may be noticeably dome shaped compared to littermates. A range of eye abnormalities is visible on a veterinary eye exam of which retinal detachment and cataracts are the most common. Carrier dogs do not have skeletal changes but may have mild eye abnormalities, including retinal folds.

Skeletal Dysplasia 2 

Skeletal dysplasia 2 is an inherited Musculoskeletal disease affecting Labrador Retrievers. Affected dogs develop a mild form of “disproportionate dwarfism” consisting of short legs with normal body length and width. The leg bones are shorter, thicker, and slightly curved and the front legs are frequently more affected than rear legs. Joints and eyes are not typically affected with this disease. The height of affected dogs is variable, making diagnosis based on physical characteristics alone challenging in some individuals. Mildly affected dogs from bloodlines known to produce large dogs may still fall within their breed standard for height. The causal Mutation shows Incomplete Penetrance meaning that not all dogs inheriting two copies (one from each parent) will display obvious physical characteristics of dwarfism

Von Willebrand Disease I

Von Willebrand disease I (VWD) is an inherited bleeding disorder affecting Labradoodles. Dogs affected with VWDI have less than half of the normal level of von Willebrand coagulation factor (vWf), which is an essential protein needed for normal blood clotting. There is variability in the amount of vWf made such that not all dogs with two copies of the Mutation are equally affected. Dogs that have less than 35% of the normal amount of vWf generally have mild to moderate signs of a bleeding disorder. Affected dogs may bruise easily, have frequent nosebleeds, bleed from the mouth when juvenile teeth are lost, and experience prolonged bleeding after surgery, trauma, or estrus. Dogs may show signs of lameness or stiffness if bleeding occurs in the joints or muscle. Less often, the bleeding may be severe enough to cause death. Due to the variable severity of the disorder, affected dogs may not be identified until a surgery is performed or trauma occurs at which time excessive bleeding is noted. Veterinarians performing surgery on known affected dogs should have ready access to blood banked for transfusions. Most dogs will have a normal lifespan with this condition despite increased blood clotting times.