
In the 60's 70's there was a lot of problems with the guide dog GSDs having HD mainly because little was known about HD then few people X rayed in the UK I know the bitches my friend had did produce some HD cases. There was also some temperament problems with the Golden x Labs they bred, we had a reject come to our training club that was basically dangerous, it had failed at the puppy walking stage & ended up being PTS as he was so unreliable
There is a lot more emphasis put on health & character now thank god, I bear the scars on my hand were I was bitten by a GD in the 60's it was a second generation from the 1st GR x Labs having been bred back to a black lab, all the GD people said was that it was my fault !
Having said that I know a blind lady who has the most gorgeous black lab guide dogs that even by BC who has bitten by a black lab as a puppy likes. She has also had a yellow lab that had to be retired early as she just did not want to be a guide dog at all. Her daughter has her & she is a lovely pet, but has no working drive at all