- Type Disease
Myelodysplasia (spinal dysraphism)
Myelodysplasia refers to a number of malformations of the spinal cord that occur as a result of abnormal pre-natal development of the neural tube (which becomes the spinal column). Lesions are most severe in the lumbar (lower back) region. See also spina bifida.
- How Transferred
In the Weimaraner, the mode of inheritance appears to be co-dominant with variable penetrance. The trait is lethal in the homozygous state (i.e.. a pup inherits the defective gene from both parents).
- What to Look for
Clinical signs usually become evident around 4 to 6 weeks when puppies begin to walk around. The signs seen with this condition vary with the severity of the spinal cord malformation. Most commonly you will see a bunny-hopping hind limb gait with or without other hind end abnormalities. \n\nThe condition is non-progressive (does not get worse) and mildly affected animals - those with a tendency to bunny-hop and a slightly awkward gait - can lead a fairly normal life.
Diagnosis is made based on the clinical signs and by ruling out other possibilities with the aid of tests such as x-rays and cerebrospinal fluid analysis. Diagnosis can also be made on post-mortem, where a veterinary pathologist will find microscopic abnormalities typical of this condition.
There is no treatment. The condition will not get worse.
- Veterinarian Information
Definitive diagnosis can only be made by histopathological examination of the spinal cord. Lesions are most severe in the lumbar region.\n\nBesides the typical bunny-hopping gait, there may be a crouching stance, abduction or overextension of one or both pelvic limbs, decreased pelvic limb conscious proprioception, or scoliosis. Spinal reflexes and pain perception are normal.
- Breeding Considerations
Affected animals should not be bred.
- Known Breeds Affected