
Figures I have at present with regards to results from eye testing for SBT-
In 2002 there were a totoal of 330 dogs/bitches tested of which 2 were found to be affected.
There were 6 affected in 2001 ( from 294 tested), 5 in 2000 ( from 277 tested) and 5 in 1999 (from 179 tested).
If you are breeding for the right reasons then any decent stud dog owner will not even think of using an untested bitch- there are far too many implications for his line and his reputation should there be affected puppies.
Persistent Hyperplastic Primary Vitreous (PHPV): Dr Barnett said that whilst a few cases of PHPV could be found in a number of dogs, inherited PHPV is found in only a few breeds, e.g. Doberman (particularly in the Netherlands where the breed was quite severely affected with PHPV) as well as Staffords. Unlike HC, which is not congenital (i.e. not present until around 3-4 weeks of age), PHPV is congenital (i.e. is present at birth). PHPV can be identified from as early as 2-3 weeks, although a more accurate diagnosis would be obtained at around 6-8 weeks of age. Although present at birth, PHPV is not progressive except in a few isolated cases, however it is very variable in its degree of severity and can affect both eyes. Dogs suffering from mild forms of PHPV can produce offspring that are severely affected.
During questioning, Dr Barnett confirmed that both PHPV and HC could be diagnosed by the age of 12-18 months. He saw no requirement, therefore, to continue testing purely for PHPV/HC after that age if previous results had been clear. However, he did emphasise that eye tests are designed to look for all eye abnormalities that may be inherited, so it is beneficial to continue testing beyond 12-18 months to regularly check for these. He recommended testing up to any age, but particularly through the breeding cycle of the dog/bitch.