Laryngeal Paralysis - Polyneuropathy (LPPN3).
The LPPN3 is another mutation that causes Laryngeal Paralysis - Polyneuropathy in Leonberger. It has also been found in Labrador Saint Bernard. Affected leonberger puppies usually develop severe symptoms of laryngeal paralysis at young age including breathing difficulty which is often loud and gagging, difficulty in swallowing food, hanges in barking frequency and quality, high-stepping and uncoordinated gait, stumbling and tripping, exercise intolerance, and muscle atrophy. In Leonberger there two more mutations known to cause the disease LPN1 and LPN2, the three tests are recommended for complete diagnosis.