Crib Biting in Horses
Cribbing is not a disease, but rather an inappropriate behavioral pattern in horses, also called "stereotypic behavior." Just as humans and other animals can sometimes exhibit obsessive-compulsive behavior that is non-lethal but still destructive, horses too will exhibit repetitive and habitual behaviors that are difficult to control.
A horse that is cribbing will place his upper incisors on a hard object, usually a pole or stall door, and suck in a large amount of air. This will make a gulping noise. The horse will do this repetitively. It is not usually related to nutritional disorders or underlying illnesses, but has been frequently linked to boredom or anxiety. Again, keeping in mind that this behavior is more of an annoyance than an actual health issue, cribbing, if left unchecked, can lead to some superficial health issues, such as the abnormal wearing of the upper incisors and enlargement of the throat muscles.
Cribbing is sometimes incorrectly called wind sucking. As the horse is cribbing, the arching of the neck causes the horse to swallow air. The correct use of the term wind sucking refers to a reproductive problem in mares.
Symptoms and Types
- Gnaw marks usually found on wood pieces, such as stall doors and fence posts.
- Top front teeth (incisors) are worn more than normally found in a horse of its age
- Arching the neck while grasping onto an object with the incisors while gulping air
- Grunting noises as the horse gulps air
Stereotypic behaviors in horses are usually caused by either boredom or stress. Horses that are highly strung and are kept in an environment with low levels of daily stimulation, such as not enough time in the pasture, are at higher risk of developing such behavioral problems. Other stereotypic behaviors include stall weaving (moving back and forth at the front of the stall repetitively), and pawing the ground. Sometimes a horse can exhibit more than one of these behaviors.
Cribbing behavior is easily visualized and therefore very simple to diagnose. Indeed, a veterinarian is not required to diagnose this behavioral problem. However, if you notice this problem in your horse, a visit from your veterinarian is a good idea, as he or she will perform a thorough physical exam on your horse, taking into account the history of symptoms to make sure there are no other underlying problems. Your veterinarian will also want to take a closer look at your horse's mouth to check for changes to the teeth. You can then work with your veterinarian to find ways to help enrich your horse’s environment and discourage the behavior.
The basis of treatment for any stereotypic behavior begins with trying to find the cause. If you and your veterinarian believe that your horse’s cribbing is due to boredom, the treatment will be to find ways to add mental and physical stimulation to your horse’s daily routine. This usually includes increasing the amount of time the horse spends in the pasture. If this is not an option, providing more roughage in the horse’s diet may also help. Giving your horse toys to play with will also help provide mental stimulation. If your horse is alone, purchasing a companion such as a goat may also help. Increasing the amount of time you spend riding and grooming your horse is also important.
If you find that your horse’s cribbing is due to anxiety, you may want to take a closer look at your horse’s routine. Some horses can become anxious when they are bored. Other horses crib out of frustration or to vent excess energy.
Other than environmental modification, there are physical means to help prevent this behavior. A piece of equipment called a cribbing strap is sometimes used. This is an adjustable strap that is secured around the horse’s throat behind his ears and jaw line. This strap prevents the horse from flexing his neck muscles as he pulls back to gulp air during the act of cribbing. This strap does not prevent the horse from eating or drinking and is not painful when the horse is not cribbing. On some horses, use of this strap is beneficial in preventing this behavior. However, it doesn’t work on all cribbers.
There are also surgical ways to prevent this behavior, although these are rarely used. These surgeries involve scarring the throat muscles so that the horse cannot flex them in the act of cribbing. This is often viewed as an extreme way of preventing this behavior, as it is often cost prohibitive since it requires general anesthesia and a visit to a specialty equine surgical facility.
Cribbing is a learned, obsessive-compulsive behavioral disorder, and can be difficult, if not impossible, to break permanently. Research has shown that cribbing results in the release of endorphins, which make the horse, feel good. To that end, horses in a way become addicted to this behavior. Even if you are able to discourage your horse from this behavior for a short period of time, the horse will, more than likely, return to the behavior once the preventive technique is removed.
Living and Management
Keeping your horse stabled too long is often what leads to this type of vice in the first place. As with many behavioral problems in domestic horses, the closer you can keep your horse in an environment that mimics a horse’s natural environment (i.e. one with plenty of access to large pastures and constant forage), the less likely the horse is to develop this condition. Whether it is from boredom, lack of nutrition, or anything else, cribbing is challenging to prevent once your horse has gotten into the habit of it. The best you can do is to give your horse enough activity to relieve it from boredom and use healthy, preventive techniques.