29-11-2017
Joppe has been tested clear for Chondrodystrophy, shortly CDDY. CDDY causes abnormal premature degeneration of intervertebral discs leading to susceptibility to intervertebral disc disease. It can also cause a short-legged phenotype.
The CDDY-test is recently developed by the Veterinary Genetics Laboratory at the University of California. Tollers can be clear (N/N), carry 1 copy (N/CDDY) or 2 copies (CDDY/CDDY). Research with other breeds showed that dogs with 2 copies always have abnormal discs but they don't always have backproblems. Dogs with 1 copy also have a higer risk of back problems.
That makes it difficult to use this test in the breedingprogramme. It is assumed that 70% of the tollers carry 1 or 2 copies of the mutation. It seems wise for now to avoid combinations of dogs that are both CDDY/CDDY. And try in the future to increase the number of N/N dogs so that we can gradually breed away from this mutation.