OverviewCribbing is an abnormal behavior of horses where the horse bites onto an object and pulls against it.
TipThese photos have captions to express any thoughts I have on the picture. The idea here is for YOU to get ideas, so grab a cup of coffee, darken the room, grab a pen and paper to write notes, and sit back and enjoy. I have more shots and I’ll add them later as I have time.
Click on any picture to see it in full size with the captions. Please enjoy and add any questions or comments below.
Please log in to see the pictures and additional content of this topic.
Cribbing is often discussed among horse owners and a lot has been said about it, but nothing has been resolved to my satisfaction as to the cause, the problems associated with cribbing, or the solution.
I think we can all agree that it is an abnormal behavior because no one has reported cribbing in horses kept in their natural state. Let me tell you what I do know.
Cribbing is the action of the horse resting the upper incisor teeth on something solid and pulling his weight down and backwards against this object. Some horses completely bite the object. Both ways adversely affect the wear of the incisor teeth causing premature tooth loss.
Some horse owners also call cribbing “wind sucking” when the horse makes a sucking of air sound while cribbing. I do not call this wind sucking because 1) the horse is still cribbing and 2) wind sucking is a term used when mares with stretched vulva lips from previous foal deliveries suck air into their uterus when running. This is an important cause of infertility and I would like to keep the expression of “wind sucking” in the reproductive meaning.
Dr Kathrine Houpt, a professor emeritus at Cornell’s veterinary school, has studied behavior in horses since I was a student there in the early 1980’s. I know how detailed she is in her data collection because I was once a student who did data collection for her. One of her projects was to determine how many times in a day a horse chewed. She had students with clickers count the chewing action of horses both stabled and turned out.
The primary result she had was that horses chewed between 10,000 and 40,000 times a day. More importantly, the lower number of 10,000 was found in horses stabled all day while the higher number of 40,000 was found with horses turned out in a field of grass. From this study I have used the number of 25,000 chews per day as the average for horses.
Just an aside here on dentistry, I find that horses turned out will have sharper teeth while horses on liquid diets and limited turn out often don’t need their teeth floated. But let me get to the observation Dr Houpt made from her chewing study.
While Dr Houpt said she had no concrete data to confirm this statement, she made an observation that horses that chewed less tended to crib more.
As a horseman and a veterinarian with decades of experience, I would tend to agree with Dr Houpt. And I have some more observations.
The insurance industry believes that there is an increased risk of colic in horses that crib. However, in my experience, there is no association between cribbing and colic. I had many horses with colic that were not cribbers and plenty of cribbers that never had colic. And the degree of colic (surgical versus non-surgical) was not associated with cribbing.
Why do horses start this bad habit that doesn’t seem to have any benefit and wears down their incisor teeth to the gums? A study was done where horses that cribbed were given an anti-narcotic. It was a drug used in opiate addiction in humans. The thought was that horses were creating an endorphin release much like humans get from similar behaviors. Apparently the researchers were correct because when these cribbing horses were given the anti-narcotic, the cribbing stopped.
The reasons why this treatment is never used is 1 – very expensive, 2 – the effect was short lived (hours), 3 – the anti-narcotic is itself addicting, and 4 – it is a controlled substance in the United States (meaning there is potential of abuse in humans with this drug). But the point remains from this study that the horse is probably cribbing from the resulting endorphin release. In other words, it is an addictive behavior.
Be sure your horses have fiber (grass or hay) to chew on at all times. If your horse has the potential to become fat on an all-access diet, then increase their exercise or use a grazing muzzle or a hay net.
If your horse already cribs, make the diet changes to increase his fiber. I also believe there is an association between a horse that cribs and a horse that is not “happy.” One of the biggest reason for a horse that isn’t “happy” is that they just don’t feel good and the biggest reason for this is that they are being fed grain. The high carbohydrate (sugar) load from grain often leads to mild to severe ulcers in the hind gut (colon) which makes the horse miserable and even leads to colic.
If I had a horse that cribs I would take away all forms of simple sugar (grain, treats, carrots, etc) and offer free choice hay or grass. I would find a way to increase the horse’s exercise and give the horse a sense of purpose.
As a last resort, I would use a cribbing collar which is a device that applies pressure to the throat area causing pain every time they crib. Many horses respond to cribbing collars and there are a lot of varieties made. While most are effective, they will permanently scar the horse and require daily cleaning to prevent sores from forming.
A few surgeries have been developed that prevent the horse from cribbing by cutting the muscles required to have the horse pull against the object he is biting. These surgeries often are not completely successful because the horse still has the addictive behavior and finds other ways or techniques to express this.
Cribbing rings have been tried by some horse owners to stop the horse by creating pain every time they brace their incisors onto the solid object. These rings can be staples or screws placed between the incisors into the gums. These are not only cruel and ineffective, they also create local infection that can lead in some cases, to the death of the horse when the infection penetrates the surrounding bone. See the pictures below of cribbing rings I have found in my practice.
Discussion to follow. If you want me to move this up on the schedule, let me know.