Headshaking
Causes
Descriptions of headshaking in horses were made as early as 1809, yet to date the causes remain uncertain. The underlying reasons for the behavior can be as diverse as the external stimuli, necessitating different curative treatments. In most cases an inflammation is the root cause of the illness: Inflamed paranasal sinuses, or oral problems in the jaw or teeth such as inflamed teeth roots, inflammation of the temporomandibular joint, infraorbital neuritis or inflammation of the accompanying vein, inflammation of the cervical vertebrae, nasal mucosa allergies, guttural pouch mycosis, ear mites, and/or light hypersensitivity. In many cases, affected horses are not acting contrary but suffer from extreme stress.
Symptoms
Headshaking, as the name already indicates, is an overreaction or abnormal behavior in a horse that arbitrarily and repeatedly shakes its head. In serious cases, the animal may even lose its balance and fall.
Consequences
Headshaking is a very serious impairment for horse and rider. For the horse it involves physical pain, as well as a progressively worsening condition. In some cases, this may progress to a point where the horse is no longer suited to be ridden.
Therapy
It is essential to check those things which can be easily eliminated, e.g. incorrect bitting, ill fitting saddles or excessive training stress. Also, check your animal's eyes, ears and teeth. A more thorough check for the root cause could include an endoscopy of the guttural pouch, the paranasal sinuses and nasal meatus, as well as a scintigraphic investigation. If your veterinarian suspects photosensitivity, he/she will anaesthetize the trigeminal nerve, the roots of which reach from the brain stem to both sides of the face all the way down to the nostrils. Headshakers suffering from light hypersensitivity must be protected from glaring lights alongside the introduction of a stress reduced environment.
