Unfortunately Leonbergers although a fairly healthy breed can suffer from some particular illnesses.

 

Many of these illnesses are said to have inherited factor but often the inheritance mode is such that it could have not been predicted and can come as a surprise to the breeder of the dog as well.  

 

If your dog suffers from one of these illnesses it is extremely important to inform the breeder. University of Minnesota also collects DNA samples and health data of any Leonberger. If the dog comes from responsible caring breeder they will want to know of any issues with the health of a puppy they have bred. We must remember we are dealing with living creatures and sometimes unexpected things do happen and there is nobody to blame.

 

If you are looking for a puppy it is important to ask the breeder the question of other "not recorded" illnesses in the line as well as hips, elbows, eyes and the genetic LPNs and LEMP - These conditions  are not the only problems Leonbergers can suffer from. Just like  with any other breed (and cross breed) there are other conditions that can have significant effect to the quality of life the dog has. I have listed some of the illnesses Leonbergers can suffer from below with short description for each.