We want to breed again this year but with Shadow being N/DM, need to know the male is N/N. So many stud dog owners seem to still be burying their head in the sand and not getting tested (and not doing so if requested!) - to quote one owner
"Of the DM test, I think myself not too much, because I look him in the breed population as inconclusive" - and his rates weren't cheap either, the test costs less than he quotes per puppy!! 
We are limited in the distance we can travel due to other responsibilities at home and need to also take into consideration the COI of any potential pairing so are getting rather frustrated...
Maybe it would be an idea to have an addition in the stud dog listings to say that the test has been done (show the results only if wanted), that way it would save a lot of time and effort for owners of females who are concientious enough to want their puppies healthy.
If stud dog owners continue to refuse to carry out the test, this disease is only going to proliferate and the outcome for the breed is not good.
Sorry for the rant but I think breeding dog owners need to wake up to the consequences of what they are (or are not) doing...