When a person becomes hoarse it is usually due to inflammation of the vocal cords which are part of the larynx. Such inflammation is known as laryngitis. Laryngitis is usually caused by viral or bacterial infection of the larynx, or voice box. The infection causes inflammation and swelling of the mucous membrane of the larynx,including the vocal cords. Continual talking, shouting or barking can also cause the larynx to become inflamed.
Dogs can develop laryngitis. When this happens, their bark usually changes pitch and you might say the dog is hoarse. I have seen this in dogs that have viral laryngitis or dogs returning from a few days at the kennel that have barked more than usual.
Your neighbor’s dogs may have been barking for so long that their larynx has adjusted, or maybe their larynx is constantly inflamed and you recognize the hoarse bark as normal.
In any case, most areas have laws about excessive noise, its called “disturbing the peace”. Contact your police department and ask what can be done to stop the noise.
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