PEMBROKE WELSH CORGI
For the most part, Pembroke Welsh Corgis are generally healthy dogs. But, like all other breeds of dogs, they are prone to certain health conditions. Not all corgis are at risk for the diseases listed below, but their breed has a history of developing them. The following paragraphs will explain some common health problems and what we do in our breeding program to help prevent our puppies from developing these problems.
Hip and elbow dysplasia are categorized as developmental disorders caused by dysmorphic and lax joint formation. This malformation consequentially results in abnormal wearing of bone over time, inducing the secondary development of osteoarthritis (OA) or arthrosis, and degenerative joint disease. Unfortunately, the pathology of neither hip nor elbow dysplasia can be reversed and so, for an affected individual, the best outcome is management of the disease through pain medication or replacement surgery, with the latter having additional consequences of cost and an extensive recovery period. Hip dysplasia is not a congenital defect; it is not present at birth. Multiple studies have demonstrated that all normal puppies are born with "perfect" hips; that is, they are "normal" for a newborn with no signs of dysplasia. The structures of the hip joint are cartilage at birth and only become bone as the puppy grows. If a puppy is going to develop hip dysplasia, the process begins shortly after birth. Hip dysplasia tends to be more common in some breeds than others and in some lines than others, which indicates that there is a genetic component to the disorder. However, scientists have been looking for genes that are responsible for the development of hip dysplasia in dogs for decades without success. Although there is a genetic influence on hip dysplasia, the heritability of the trait is rather low. Many studies have shown that genetic variation accounts for only a modest fraction of the variation in hip scores, usually 15-40%. This means that some fraction of the variation in the quality of the hips is the result of non-genetic, or "environmental" influences. This is one reason why decades of strong selection has resulted in only modest reductions in hip dysplasia in some breeds. At the current rate of progress and selecting only by phenotype, it could take decades to achieve a meaningful reduction in the incidence of hip dysplasia. The top three environmental factors that have been found to play a significant role in the develop of dysplastic hips are: a) joint laxity, b) weight, and c) exercise.
Laxity- Puppies are born with perfect hips, and if the hips do not develop laxity the dog does not develop hip dysplasia. Joint laxity occurs when the head of the femur does not fit snugly into the acetabulum. This could be the result of traumatic injury, overloading of the joint by weight, lack of muscle strength, or adductor forces. Joint laxity is the primary factor that predisposes a dog to the development of hip dysplasia.
Weight-If there is laxity in the hip joint, the amount of damage done to the femur and acetabulum will depend on the magnitude of the forces in the hip joint. The heavier the dog, the greater the forces will be and also therefore the higher the risk of hip dysplasia and osteoarthritis. Growing puppies need to eat enough to support growth but they should not be fat, because any extra weight can increase the risk of developing hip dysplasia. At four years old, less than 10% of dogs kept on a restricted diet (25% less than the control diet) were dysplastic, while at the same time more than 30% of the dogs in the control group were dysplastic. As an added advantage, dogs on restricted diets live longer, too. Unfortunately, many dogs (including show dogs!) are overweight, and obesity could well be the single most significant environmental factor affecting the development of hip dysplasia and osteoarthritis. But body weight is a factor that we can control! Although progress from genetic selection will take many generations, the incidence of hip/elbow dysplasia in dogs could be immediately and dramatically reduced simply by practicing better weight management.
Exercise- Exercise strengthens the muscles of the legs and pelvis, and this will increase the stability of the hip joint. But all exercise is not created equal. Puppies raised on slippery surfaces or with access to stairs when they are less than 3 months old have a higher risk of hip dysplasia,while those who are allowed off-lead exercise on soft, uneven ground (such as in a park) have a lower risk. Dogs born in summer have a lower risk of hip dysplasia, presumably because they have more opportunity for exercise outdoors. On the other hand, dogs from 12-24 months old that regularly chase a ball or stick thrown by the owner have an higher risk of developing dysplastic hips. The type of exercise puppies are exposed to from a very young age is very important in increasing the risk for hip/elbow dysplasia.
At Maverick Ranch we have our dams and sires hips and elbows evaluated by the Orthopedic Foundation for Animals. Hip/Elbow Radiographs are taken and submitted to the OFA for reviewing. The OFA grades their hips in categories of Severe, Moderate, Mild, Borderline, Fair, Good, or Excellent. Preliminary OFA grades can be done before two years of age, but final OFA results must be done after two years of age. The OFA has approximately 14, 000 Pembroke Welsh Corgi hip screenings recorded, of that 20.4% had abnormal results. The OFA has approximately 1,400 Pembroke Welsh Corgi elbow screenings recorded, of that 4% were abnormal. We also take great care to make sure our puppies are raised on grippy surfaces from day one, get proper nutrition and diet, and get puppy-appropriate exercise. Even taking all of these precautions, the risk of hip and elbow dysplasia cannot currently be eliminated.
Degenerative Myelopathy (DM)
The dog equivalent of Amyotrophic Lateral Sclerosis, or Lou Gehrig’s disease, DM is a progressive degenerative disorder of the spinal cord. Because the nerves that control the hind limbs are the first to degenerate, the most common clinical signs are back muscle wasting and gait abnormalities. Affected dogs do not usually show signs of DM until they are at least eight years of age. 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. As dogs are seniors at the time of onset, the treatment for DM is aimed towards increasing their comfort through a combination of lifestyle changes, medication, and physical therapy.
Degenerative Myelopathy is a recessive inherrited gene, meaning a puppy must carry two copies (one from the dam and one from the sire) to be at risk for developing DM. The overall frequency of this disease is unreported in Pembroke Welsh Corgis. However, in one study of 3209 Pembroke Welsh Corgis tested, 28% were carriers of the mutation and 65.1% were at-risk/affected.
At Maverick Ranch all of our Pembroke Welsh Corgi dams and sires are genetically tested for this mutation. Our breeding program will NEVER produce puppies that are at risk for this mutation. Currently, our breeding program will only produce puppies that are genetically carrier or clear.
Von Willebrands Disease Type I (VWDI)
Von Willebrand Disease I (VWDI) is an inherited bleeding disorder affecting Pembroke Welsh Corgis. 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 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 or trauma. 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.
Von Willebrands Disease is a recessive inherited gene, meaning a puppy must carry two copies (one from the dam and one from the sire) to be at-risk for developing the disease. Although the frequency of this disease in the corgi population is unknown, 37% of Pembroke Welsh Corgis tested for the disease were carriers for the mutation and 6% were at-risk/affected.
At Maverick Ranch all of our Pembroke Welsh Corgi dams and sires are genetically tested for this mutation.Our breeding program will NEVER produce puppies that are at-risk for this mutation. Currently, our corgi breeding program will only produce puppies that are genetically clear.
Exercise Induced Collapse (EIC)
Exercise-Induced Collapse (EIC) is an inherited neuromuscular disorder affecting Pembroke Welsh Corgis. 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.
Exercise Induced Collapse is a recessive inherited gene, meaning in general a puppy must carry two copies (one from the dam and one from the sire) to be at-risk for developing the disease. The frequency of this disease is unknown in Pembroke Welsh Corgis. A group of 94 Pembroke Welsh Corgis were tested for the mutation and 14% tested as carriers and 2% tested at-risk for the developing the disease.
At Maverick Ranch all of our Pembroke Welsh Corgi dams and sires are genetically tested for this mutation. Our breeding program will NEVER produce any puppies that are at-risk for this mutation. Currently, our breeding program only produces puppies that are genetically clear.
Progressive Retinal Atrophy, Rod Cone Degeneration (PRA-rcd3)
Progressive Retinal Atrophy, Rod-Cone Dysplasia 3 is an inherited eye disease affecting dogs. Progressive Retinal Atrophy, Rod-Cone Dysplasia 3 is an early onset disease affecting the Photoreceptor Cells of the Retina and results in the progressive loss of vision. Affected dogs have abnormal thinning and degeneration of the retina beginning around 4 weeks of age. Signs of progressive retinal atrophy including changes in reflectivity and appearance of a structure behind the retina called the Tapetum that can be observed on a veterinary eye exam by 6 to 16 weeks of age. Rod photoreceptor cells degenerate first resulting in loss of peripheral vision and night vision. As the disease progresses, cone photoreceptor cells also degenerate resulting in complete blindness. Most affected dogs are completely blind by 1 year of age, but some may retain limited sight until 3 to 4 years of age.
Progressive Retinal Atrophy is a recessive inherited gene, meaning a puppy must carry two copies (one from the dam and one from the sire) to be at-risk for developing the disease. The frequency of this mutation is unknown in the Pembroke Welsh Corgi.
At Maverick Ranch all of our Pembroke Welsh Corgi dams and sires are genetically tested for this mutation. Our breeding program will NEVER produce puppies that are at-risk for this mutation. Currently, our breeding program only produces puppies that are genetically clear.
Severe Combined Immunodeficiency Disease, X-linked (X-SCID)
X-linked severe combined immunodeficiency (corgi type) is an inherited disease affecting Pembroke Welsh corgis. Affected dogs are unable to produce a protein important for proper immune function, predisposing them to severe recurrent or chronic bacterial, viral and fungal infections. Affected dogs often present with symptoms of disease around 6 to 8 weeks of age including failure to thrive, poor growth, weight loss, lethargy, diarrhea, vomiting and lack of palpable lymph nodes. Affected dogs may also present with active respiratory, skin, eye or ear infections. Affected dogs die within 4 months of age.
X-linked severe combined immunodeficiency (corgi type) is inherited in an X-Linked Recessive manner. Females must receive two copies of the mutated gene (one from each parent) to develop the disease while male dogs only require one copy of the mutated gene from the mother in order to develop disease. Therefore, male dogs more commonly present with symptoms of the disease.The mutation of the IL2RG gene associated with X-linked severe combined immunodeficiency disease has been identified in Pembroke Welsh corgis, although its overall frequency in this breed is unknown.
At Maverick Ranch all of our Pembroke Welsh Corgi dams and sires are genetically tested for this mutation. Our breeding program will NEVER produce puppies that are carriers or at-risk for this mutation. Because this mutation is x-linked, we will only produce puppies that are genetically clear.
Intervertebral Disc Disease
Type I Intervertebral Disc Disease (IVDD) is a back/spine issue that refers to a health condition affecting the discs that act as cushions between vertebrae. With Type I IVDD, affected dogs can have a disc event where it ruptures or herniates towards the spinal cord. This pressure on the spinal cord causes neurologic signs which can range from a wobbly gait to impairment of movement. IVDD is treated differently based on the severity of the disease. Mild cases often respond to medical management which includes cage rest and pain management, while severe cases are often treated with surgical intervention.
Research indicates that dogs with one or two copies of this variant have a similar risk of developing IVDD. However, there are some breeds (e.g. Beagles, Cocker Spaniels, and Corgis, among others) where this variant has been passed down to nearly all dogs of the breed and most do not show overt clinical signs of the disorder. Nearly 100% of the dogs in some short-legged breeds have two copies of this mutation (e.g. dachshund, corgis), making it virtually impossible to breed away from this mutation in these breeds. This suggests that there are other genetic and environmental factors (such as weight, mobility, and family history) that contribute to an individual dog’s risk of developing clinical IVDD.
Although the inheritance risk of this mutation is not fully understood, it is important to recognize the risk. Nearly all corgis carry this mutation because it is linked to the mutation that gives corgis their distinct build and appearance. Because of this, environmental preventative steps need to be taken with Pembroke Welsh Corgi dogs.
At Maverick Ranch, we try to educate our puppy buyers about weight management and proper corgi exercise to help reduce the environmental risks for this disease. Corgis dogs should always have their weight managed and avoid jumping and flights of stairs.
The #1 health problem facing corgis today is obesity. Society has normalized fat dogs, and many pet owners don't know what the proper body score should look like. By using phrases like "thick","chonker", and "big-boned" we've altered the perception of a healthy dog. We can no longer see the extra weight for what it is, dangerous. It's very important to monitor your dog's calorie intake and adjust it accordingly. Pembroke Welsh Corgis should NEVER be fed free choice. Corgis love to eat, and given the chance will get very fat. Sadly, obesity can also lead to an increased risk of heart disease, diabetes, hip dysplasia, intervertebral disc disease, and joint damage, among other things. It is the responsibility of the dog owner to give their dog the proper amount of food, because their dog's health depends on it.
At Maverick Ranch we try to educate our puppy families on proper nutrition and weight management. We give our puppy families information on our "Puppy Manual" page to help explain proper body score and how to tell what score your dog or puppy is.
Information on this page is sourced mostly from Paw Print Genetics, Embark Vet and the OFA