Stable Vices in Horses - Why Do They Do It And How Can We Stop Them?
What Is A Stable Vice?
A stable vice is an unnatural behavior observed in a horse that is stabled or stalled for extended periods of time. These behaviors are disturbing to humans that observe them and may negatively impact the animal's health.
Stable vices are normally the result of boredom, stress, or loneliness, or any combination of the three. I have also seen them develop in horses that have been neglected or starved.
Why Do They Do It?
Stable vices are behaviors that release endorphins. That means it feels good to the horse and the horse can even become physically addicted to the behavior. This makes an established stable vice almost impossible to cure - the horse will continue with the behavior long after the initial cause for it is removed.
Cribbing and Windsucking
The first of the two stable vices is cribbing or windsucking. When a horse cribs, it grabs a horizontal bar or plank with its teeth and sucks air rapidly through its mouth, arching its neck. A windsucker has learned how to get the same effect without needing a bar or plank. Cribbing can cause excessive tooth wear and some people feel it makes a horse a poor keeper. This is more likely because of the horse cribbing when it could and should be eating than any direct effect of the behavior, however. Severe cribbers may also show signs of fatigue, possibly because they are cribbing instead of sleeping.
The early stages of cribbing can often be nipped in the bud by applying a vile tasting substance to any surface the horse might use to crib. Soap, hot sauce and bitter lemon all work well. Some people use a grazing muzzle, but I have seen a determined cribber wriggle part of the way out of one and keep right on cribbing.
A crib strap is a traditional preventative. The strap is fastened around the horse's throat and has a blunt metal piece on the underside that digs in to the animal if it arches its neck to crib or windsuck. However, some horses will learn to ignore the crib strap, it can be hard to fit correctly and some people believe that they are cruel or potentially damaging. They can also rub a horse - if you do use one I recommend wrapping fleece around both of the top straps to prevent rubbing and hair loss. (Others go to the other extreme and try to use shock collars, which do not work well).
Weaving And Stall Walking
A horse that stall walks walks around the stall constantly, just as you might pace when thinking about something. A weaver will stand in one place and rock from side to side. Most weavers will put their head over the door to weave, but I have seen horses weave even when locked in behind a grill.
Weaving causes uneven hoof wear and may make certain chronic lameness conditions worse. It is also absolutely horrible to watch. Weavers will often stop if you go over and pet them, then start up again as soon as you leave. Stall walkers may also literally wear a groove in the stall floor.
Note that a horse that stall walks when you come down the aisle with everyone's grain and only at that time is simply displaying impatience. This behavior, and the annoying habit of banging on the door when the feed is coming can often be stopped by consistently feeding any horse that misbehaves last. They will learn fairly quickly.
Weaving is strongly associated with isolation. Some racehorse trainers have cured it by putting a goat or even a chicken in the horse's stall with them. I have also heard that a plastic mirror hung in the stall can stop weaving, although I haven't seen this work myself.
The best preventative is the same for both kinds of stable vices - lots of turnout, preferably with other horses. I have also seen both behaviors reduced by giving a horse more interesting work. Getting out of the arena every so often is very helpful for both your horse and you.
A die-hard cribber will still crib in the paddock - I honestly feel there is a point at which this habit can't be fixed at all, and just has to be lived with. In our barn there is one mare who was starved...this is the mare I witnessed wriggle out of a grazing muzzle that was supposed to stop her cribbing. She also would completely ignore the action of a crib strap. I believe that she developed the habit to suppress her appetite when she was not being fed. She was also severely depressed when she arrived in the barn as well as being a BCS somewhere between 2 and 2.5. She's now what I would call a confirmed cribber and is probably incurable. Fortunately, the habit does not harm them as much as we think it does.
I will note that I have not seen an increase in stable vices associated with the use of standing stalls as opposed to box stalls. If anything, it almost appears that horses kept in box stalls demonstrate these behaviors more. Another thing to consider is using the open design stalls with bars, so horses can see their neighbors. The only time I feel a stall should be solid is if it is being used as a quarantine stall or a foaling stall (mares prefer not to be observed when foaling, either by other horses or by humans - every breeder has a story from the pre CCTV days that begins 'I just got up to get a cup of coffee...)
Horses on twenty-four hour turnout will never develop stable vices, but many urban barns do not have enough grazing to achieve this ideal.