Head Shaking May Have a Variety of CausesBy Kentucky Equine Research Staff · October 29, 2002
All horses shake or toss their heads from time to time. Some horses, however, exhibit the behavior far more often than others. In cases where head shaking is so frequent or violent that it interferes with the horse's comfort or use, an effort should be made to uncover and eliminate the cause. Tracking down the reason for this annoying (and occasionally dangerous) behavior can be a lengthy and difficult chore. Asking questions about the horse's habits is the first step in solving the puzzle.
Does the horse toss his head only when ridden?
In horses that toss or shake their heads only when ridden, the problem may be caused by pain. Have an equine dentist do a thorough oral exam to make sure the teeth do not have sharp points or edges that are irritated by the pressure or position of the bit. In young horses, the shallow-rooted wolf teeth sometimes interfere with the bit and can easily be removed by a dentist or veterinarian.
Subtle lameness or back pain can be a cause of head tossing as the horse tries to find relief from discomfort. If the behavior occurs when the horse is asked to flex or work in a collected frame, consider more breaks where your mount can relax and stretch his neck for a few moments.
Watch while a trainer or more advanced rider gets on the horse. No owner likes to hear that his rough hands are the problem, but if the horse goes well for another person, a subtler touch on the reins may eliminate head tossing.
Tiedowns, martingales, side reins, and more severe bits usually don't fix head shaking. Paradoxically, some difficult horses perform better in a milder bit (thicker mouthpiece, shorter shanks) rather than one that promises more control. Other horses that fuss and fidget with a bit are far more contented when ridden in a bosal, hackamore, or side-pull bridle. It goes without saying that any bit should be properly fitted so that it does not pinch the horse's mouth. If you aren't absolutely certain the bit is the right size or in the right position, ask a trainer for help.
Other reasons for head tossing or shaking may be high energy levels at the beginning of the ride or resentment of whip or spurs. A period of turnout or longeing before a ride can help an energetic horse settle into his work. A trainer may be able to evaluate the use of, and the horse's response to, spurs and whip.
Does the horse toss or shake his head in the field or stall as well as under saddle?
Some horses are extremely sensitive to strong sunlight. Exposure to bright light causes a nerve in the head to send a shock-like sensation to the horse's face, and he reacts by violently flinging his head up and back. This type of head shaking is typically worst in the summer but is also seen on bright winter days. A horse with this condition, called photic head shaking, may also sneeze or snort frequently, and may try to rub his nose or face against his legs or other objects. Affected horses like to stand in the shade or at least keep their heads shaded by a barn, hedge, or pasture buddy. Some owners have found that the behavior stops if the horse wears a facemask to shade the eyes.
The drug cyproheptadine has been effective in relieving the problem in some horses, and a combination of cyproheptadine and carbemazepine has been helpful in others. Still other horses have shown a dramatic improvement with the addition of a fringe, net, or solid covering over the lower part of the face. A popular trick is to cut a tube of mesh from stockings or pantyhose and to sew it to the noseband of the bridle or halter so that it gently hugs the horse's muzzle. Although no one is sure why this helps, the theory is that the sensation of a fringe or net interrupts the annoying and painful nerve signal. Yes, it looks strange, but the horse's relief is so obvious that it might be worth a try!
Because of the structure of the horse's ear, bacterial or fungal infections of the middle or inner ear sometimes fail to clear up on their own. Chronic inflammation leads to changes in the bony structures, irritating nerves that pass through the area. Head shaking is an early indication of this problem, which sometimes progresses to abnormal head carriage, facial paralysis, and numbness. A veterinarian can diagnose this condition which can be treated by the surgical removal of the affected bone.
Irritation of the ears because of mites, ticks, and other insects can cause a horse to toss his head. Tumors within the ear are another possible cause. A veterinarian can often pinpoint the problem and suggest treatment and prevention measures.
Some horses have tiny retinal fragments or bits of tissue floating in the jellylike substance within the eye. One theory to explain head tossing is that, as the horse exercises, these “floaters” change position, suddenly entering the field of vision and causing the horse to throw his head up and away from what he perceives as a threat.
Some studies of head-shaking horses have indicated that geldings are affected about twice as often as mares, while others have shown no bias by sex, breed, or age. Allergies, infections, resistant behavior, and a multitude of other factors have been proposed as causes of the behavior, and many treatments have been attempted with varying results. In some horses, the reason for head shaking can never be positively determined.
So what can you do if your horse is a head-shaker?
Here's a summary of steps to take.
Try to determine the circumstances that trigger head shaking. Begin by following the suggestions in the early part of this article.
Describe the problem to your veterinarian and ask him to conduct a thorough examination. This may involve tests for lameness or stiffness, nerve blocks of the facial area, and trials of various medications.
Ask an equine dentist to examine your horse and treat any abnormalities.
For further ideas, or just some sympathy and support, contact one or more of the Web sites devoted to equine head shaking.