Update :
In the meantime I did find out there are indeed CsW’s with Degenerative Myelopathy
This genetic disease inherited in the same way as for example pituitary dwarfism.
To ban this disease in future, the only thing is not to make any longer crossings between carrier x carrier!(of this mutated gen)
Because of a simple test can be established if a dog is carrier of this mutated gene. 
The “van Haeringen lab (in Holland) has developed a test, which can determine the mutation of the gene that is responsible for DM.
This test is already available for SWH and German shepherd breed.
And it is probably also possible to validate this test for CsW breed!
So I ask your help for the validation of the DM test for the CsW breed!
When you have or know a CsW with DM and you want to cooperate with the validation of this test, please contact me: mijke@wolfdog.org
@Martial: Please can you transtale this and add also on the French forms?
thanks in advance!