This is advice for you the puppy buyer to take wherever you go to look for a puppy, either here at Vonstarlite or elsewhere. Ask the breeder if the puppies’ parent are tested for DM and to see the test results.
All German shepherds are susceptible to this disease no matter the bloodlines, they must be tested in order to know if they carry for it or not. The only way to know for sure is if they tested the parents of the puppies, SO ASK FOR THE PROOF!! If someone is advertising they are DM Free kennel they should readily show you the proof of the testing done on their breeding dogs, if there is no DM testing done then you should walk away if the heartache of Degenerative Myelopathy is something you are trying to avoid for you and your dog.
What is Degenerative Myelopathy?
Canine Degenerative Myelopathy (also known as Chronic Degenerative Radiculo Myelopathy) is a progressive disease of the spinal cord in older dogs. The disease has an insidious onset typically between 5 and 14 years of age. It begins with *hindquarter weakness, rear limb ataxia (reflex to right foot when turned backwards, slow, or nonexistent), loss of balance, difficulty rising or laying down, knuckling under while walking, limp tail, rear legs crossing under body, rear leg drag, spinal ataxia, hoarseness of bark, leading to paralysis, and incontinence in the final stages... The affected dog will wobble when walking, knuckle over or drag the feet. This can first occur in one hind limb and then affect the other. As the disease progresses, the limbs become weak and the dog begins to buckle and has difficulty standing. The weakness gets progressively worse until the dog is unable to walk. The clinical course can range from 6 months to 1 year before dogs become paraplegic. If signs progress for a longer period of time, loss of urinary and fecal continence may occur and eventually weakness will develop in the front limbs. Another key feature of DM is that it is not a painful disease.
What causes Degenerative Myelopathy?
Degenerative myelopathy begins with the spinal cord in the thoracic (chest) region. If we look under the microscope at that area of the cord from a dog that has died from DM, we see degeneration of the white matter of the spinal cord. The white matter contains fibers that transmit movement commands from the brain to the limbs and sensory information from the limbs to the brain.
DM vs Normal
In the section of a spinal cord from a dog who has died of DM (Left), the degeneration is seen as a loss of the blue color at the edges (arrows) compared with the spinal cord from a normal dog which is blue througout (Right).
This degeneration consists of both demyelination (stripping away the insulation of these fibers) and axonal loss (loss of the actual fibers), and interferes with the communication between the brain and limbs. Recent research has identified a mutation in a gene that confers a greatly increased risk of developing the disease.
How do we treat degenerative myelopathy?
There are no treatments that have been clearly shown to stop or slow progression of DM. Although there are a number of approaches that have been tried or recommended on the internet, no scientific evidence exists that they work. The outlook for a dog with DM is still grave. The discovery of a gene that identifies dogs at risk for developing degenerative myelopathy could pave the way for therapeutic trials to prevent the disease from developing. Meanwhile, the quality of life of an affected dog can be improved by measures such as good nursing care, physical rehabilitation, pressure sore prevention, monitoring for urinary infections, and ways to increase mobility through use of harnesses and carts.
DNA Testing Information for Degenerative Myelopathy
Here the very well explained graph of results from VET DNA CENTER when all progeny is tested from one litter of a certain combination, thus even when an At Risk parent is bred to a Carrier Parent, the result can still be 50% or half of the pups born are clear (fortunately) However, the other half will be at risk and not worth the chance to take for any caring and careful breeder.
On the other hand, if a breeder has a top rated male or female which tested AT RISK, (do not panic) then when bred to a NORMAL mate only, this combination will only produce CARRIER offspring, thus this offspring can then be bred to a NORMAL mate, test ALL offspring and choose pups which tested NORMAL only for furthering the breeding program and thereby the breeder can quickly breed out DM in its entirety.
Degenerative Myelopathy is a debilitating disease that causes gradual paralysis in many dog breeds. It is caused by a degeneration of the spinal cord that onsets typically between 8 and 14 years of age. It presents first with the loss of coordination of the hind legs. It will typically worsen over six months to a year, resulting in paralysis of the hind legs. If signs progress for a longer period of time, loss of urinary and fecal continence may occur and eventually weakness will develop in the front limbs. An important feature of DM is that it is not a painful disease.gsd_theo
Explanation of DNA Test Results
This dog is homozygous N/N for the mutation that is the most common cause of DM, with two normal copies of the gene. Among the hundreds of dogs studied so far at the University of Missouri, only two dogs with test results of N/N (Normal) have been confirmed to have DM. The N/N (Normal) dog can only transmit the normal counterpart of the common mutation to its offspring, and it is unlikely that this dog or its offspring will ever develop DM.
This dog is heterozygous A/N, with one mutated copy of the gene and one normal copy of the gene, and is classified as a carrier. Carriers are far less likely to develop DM, but we have confirmed DM in a few carrier dogs. They may be used carefully in breeding programs to keep their good qualities while reducing risk of DM in future generations.
This dog is homozygous A/A, with two mutated copies of the gene, and is at risk for developing Degenerative Myelopathy (DM). Although almost all dogs in the research study with confirmed DM have had A/A DNA test results, recent evidence suggest that there are other causes of DM in some breeds. In addition, not all dogs testing as A/A have shown clinical signs of DM. DM is typically a late onset disease, and dogs testing as A/A that are clinically normal may still begin to show signs of the disease as they age. Some dogs testing A/A did not begin to show clinical signs of DM until they were 15 years of age. Research is ongoing to estimate what percentage of dogs testing as A/A will develop DM within their lifespan. At this point, the mutation can only be interpreted as being at risk of developing DM within the animal’s life. For dogs showing clinical signs with a presumptive diagnosis of DM, affected (A/A) test results can be used as an additional tool to aid in the diagnosis of DM. Dogs testing At-Risk (A/A) can only pass the mutated gene on to their offspring.
* What DM means to you and your breeding program
We are a breeder looking to ELIMINATE the possibility of producing AT RISK puppies in our breeding program, then breeding to a CLEAR parent is the first step. By breeding your dog to a CLEAR parent we are ASSURED that EVERY puppy produced from that breeding will be FREE of the risk of developing Degenerative Myelopathy. Our males has been DNA tested CLEAR, therefore they will never produce any AT RISK offspring no matter if they is bred to an AT RISK or CARRIER female.
You can do your part in helping to reduce this debilitating disease in our great German Shepherd breed by choosing to breed your female to a CLEAR tested male.
Any of our breeding dogs' DM test can be reviewed by request.