Which of the following is NOT a symptom of distemper?

Hearing loss is not a typical symptom associated with distemper. Canine distemper is caused by a virus that primarily affects the respiratory, gastrointestinal, and central nervous systems of dogs, along with some other signs that impact their overall health.

Hardened footpads, weight loss, and nasal discharge are all common symptoms of distemper. Hardened footpads result from the virus causing changes in the skin and immune response. Weight loss often occurs due to the virus affecting the dog's appetite and metabolism, as well as causing gastrointestinal distress. Nasal discharge is also a well-documented symptom, reflecting respiratory involvement as the virus affects the dog’s upper respiratory system.

In contrast, while neurological symptoms can arise later in the disease, direct hearing loss isn't typically classified as a primary symptom. The presence of neurological complications may lead to issues that indirectly affect behavior or sensory perception, but hearing loss itself is generally not listed among the hallmark signs of distemper.