Respiratory conditions, chronic vomiting, trauma to the larynx or trachea, and metabolic disorders are all possible medical reasons why a dog doesn't bark. Anything that affects the larynx (voice box) can make it painful and even impossible for a dog to bark. Laryngeal disease is one of the most common culprits.

Is it unusual for a dog not to bark?

Each dog has his or her own personality. Some dogs may not like the sound they make when barking or he may prefer to whine or make whimpering sounds. Your dog may be laid-back and easy-going and feel no need to bark. There are conditions that can lead to your dog not barking.

What is a dog that doesn't bark called?

The basenji is literally known as the "barkless dog," but the breed's not completely mute.