Stereotypic behavior is the preferred term for behaviors that are often referred to as stable vices. Stereotypies are of concern because of the damage the horse can do both to itself and to its environment. Stereotypies are seen by most researchers and horsemen as safety valves that allow a horse to survive stress without becoming neurotic.
Any repetitive behavior performed with no obviously discernible function.
Dr. Georgia Mason, 1991
Researchers usually categorize stereotypic behaviors into three different areas including oral, locomotor, and other. The oral behaviors relate to a horse using its mouth or teeth in a repetitive way, while locomotor behaviors relate to movement of the horse, and "other" behaviors include any repetitive behavior in any other mode.
Simple attempts to curb or stop the behaviors may cause more damage than the stereotypy itself. Development of a stereotypy in most cases acts as a warning that the horse is in a frustrating environment and needs to release pressure. The movements and actions involved in the particular stereotypy help the horse to do so.
As a horse owner, you can work most effectively to keep your horse or horses from developing stereotypies by:
- Recognizing common causes and symptoms of stereotypies
- Identifying the types of environment in which they are common
- Looking for welfare indicators in your horses such as physiological signs of stress that might lead to stereotypies
- Taking positive steps to keep the environment for your horse as positive and natural as possible.
Although these steps may not totally prevent your horse from developing a stereotypy, they will certainly minimize the chances of that happening.
Basic Causes of Stereotypic Behaviors
Research and observation reveal at least eight basic causes of stereotypies and include the following:
- Confinement: According to Mason, 1991, and Miller, 1996, the development of a stereotypic behavior such as cribbing is associated with the degree of confinement. Because of insufficient stimuli including activity in the horse's field of vision and its contact with other horses, the animal turns to rewarding self-stimulation. Stereotypies are rare in horses that are not confined and either reduce in frequency or disappear completely when horses are given more space and stimulation.
- Lack of Socialization: Horses are naturally herd animals and are very social. When housed separately, especially when they can't see other horses, it is very stressful to them and horses that spend most of their time in isolation have a difficult time adjusting to many situations. They may be overly aggressive or extremely reclusive.
- Temperament: Some horses become severely stressed by any slight changes in their daily routines. Others remain accepting and relaxed no matter what happens. A sensitive, high-strung horse is more likely to develop stereotypic behavior when either over or under stimulated.
- Boredom or over stimulation: If a horse's life is dull and monotonous, boredom can lead to development of repetitive behaviors to fill the time and relieve tension. On the other hand, if a horse is over stimulated, with too many people and horses around, the accompanying stress can lead to a need to find relief in the same way people turn to biting fingernails, twisting her hair or engaging in other tension-relieving motions.
- Sudden changes in routine: Routine changes can be stressful for many horses. Normally, horses appear to fall into a rhythm when daily activity follows a pattern in feeding, grooming, riding, and other activities. When the pattern is interrupted or changed because of an injury, being moved, a dramatic change in training, or another change, some horses appear to become very nervous and stressed leading to repetitive actions in which to take some kind of comfort.
- Unnatural feeding schedules: Horses naturally prefer to graze as opposed to bulk feed meals twice a day. Many horses eat their feed in a relatively short time leaving them little to do for hours on end, especially if they are in a stall most of the day. These structured, relatively brief feedings do not meet the horse's instinctive urge to forage for food. Research indicates that feeding two bulk meals a day with nothing to nibble on for many hours causes some horses to develop stereotypies involving their lips and mouth.
- Unnatural Feeds: When horses are fed mostly concentrated feed in quantities larger than the amount needed for the work they do, they tend to develop active stereotypies, possibly as a way to work off the energy content of the feed. Highly concentrated feeds also have less roughage than regular hay and feed which reduces the volume of feed and the time a horse spends eating it.
- Insufficient Exercise: Too little exercise can lead to boredom, but more importantly, too little exercise leaves a horse with pent-up energy that needs to be expended in some way. This excess of pent-up energy may cause the horse to become hyper and it may buck or rear and make the riding experience unpleasant. As a result, the horse may be taken out less frequently which only compounds the problem. Stall walking and weaving are stereotypies often identified with insufficient exercise.
In addition to the eight commonly recognized causes of stereotypic behavior, several other causes are noted both in research and from experience as contributing factors.
- Uncomfortable stall situation: Living day in and ay out in a stall that has too much or too little light, poor ventilation, drafts, a constant low or high temperature, poor bedding conditions or is uncomfortable in other ways may cause a horse to perform repetitive movements that become stereotypies.
- Genetics: Some horses in family lines seem to be prone to developing stereotypies leading people to believe that genetics are involved in causing a horse to engage in stereotypic behaviors. It is more likely that nervous, sensitive or high-strung horses in a family line will perform the same job as their parents and ancestors. Since they are subjected to the same kinds of living circumstances including living conditions and feed programs, they may react by engaging in stereotypic behavior as their ancestors did before them. A colt might pick up a weaving habit from its mother due to living in the same conditions, but there may also be a genetic predisposition to it.
- Mimicking: Although some people believe that horses pick up bad behaviors, mannerisms or habits by copying other horses, the jury is still out. It is true that horses learn aggressive behaviors from each other, but so far there has been no published research that shows horses learn either good or bad behaviors from watching other horses. In experiments horses have watched other horses being trained and horses have watched other horses engaging in stereotypies such as cribbing, yet neither behavior appeared to be adopted.
Since stereotypies rarely occur in horses living in a relatively rich environment that is appropriate for horses and where a wide range of behaviors occur with plenty of social interaction, it is believed by most people and researchers that stereotypies result from a horse being kept in an unnatural environment that affects the horse's welfare.
Additional research shows that horses that perform stereotypies, show fewer physiological signs of stress than horses that are obviously stressed, but don't engage in stereotypic behaviors (Wiepkema et al 1987).
Unfortunately, once a horse begins engaging in stereotypic behavior, getting it to stop can be extremely difficult. Past experience and research show that attempting to block stereotypies doesn't work. Researchers and horsemen agree that maximizing the horse's welfare is the most effective way of preventing stereotypic behaviors.
The best plan of action is to determine the specific cause or causes of the behavior and then address those causes by removing them or mitigating the effects they have on the horse.
Preventing Stereotypic Behaviors
Here are eight steps you can take either to prevent horses from developing stereotypic behaviors or to eliminate them:
- Stabling horses together in freely associating groups or with family groups allows the contact necessary to prevent the development of stereotypic behaviors. Horses that interact with each other are able to hear, touch, smell and interact with each other frequently and is considered one of the most healthy ways for horses to live. It is best when a horse is introduced to a group at an early age. This reduces any threats of aggression or injury that can be the result of older horses being artificially grouped.
- Provide as much visual stimulation as possible with windows in stalls and a clear view of other horses if a horse is restricted to the stall for much of the day. Break-proof mirrors and appropriate lighting also may be useful in providing stimulation for the horse.
- Provide plenty of hay throughout the day when a horse is confined to a stall for long periods of time. Automatic feeders are on the market that can save both time and effort in making a more natural feeding schedule available for your horse. Having to tug hay out of a hay net over a period of time will provide the horse with actions similar to foraging, as well as lengthen feeding time.
- Make sure that your horse receives sufficient exercise at least six days a week. Although a minimum of 30 minutes a day is recommended, a couple of hours are better for many horses. If you are not available to ride your horse or exercise it, hire a neighbor or another interested and responsible person to ride or lunge the horse for you.
- Give your horse as much turn-out time as possible even in cold weather. If your horse has access to a pasture, this can be the best of all worlds for the horse since it can provide stimulation, exercise, grazing opportunities and socialization either with other horses or with people.
- Make sure that your horse has an adequate diet including plenty of roughage, a salt lick and supplements where necessary along with feed that provides plenty of chewing.
- Consider providing another animal for companionship if your horse does not have stable mates or other horses with which it can interact. A goat, chickens, a donkey--any animal that provides diversion and company, but that won't be stepped on or escape from the stable can work as a companion for a horse.
- Invest in stable toys for your horse. Although the jury is still out on whether or not stable toys reduce incidents of stereotypic behavior, feeding balls that dribble out small amounts of feed and can be pushed around will keep the horse engaged and having to "forage" for feed may be helpful.
Maximizing the horse's welfare is the most effective way of preventing stereotypic behaviors.
Horse welfare is the key to the prevention of stereotypies. Housing, management, social contact among horses, proper nutrition, sufficient exercise, physical comfort, and weaning methods are seen as influential factors in the development of stereotypic behaviors, although breed and behavior of the dam may, in some cases, be an influence.
Stereotypic behaviors affect a horse's usefulness, dependability and health. Once established these bad habits are difficult to eliminate and may lead to physiological problems. Many stereotypic behaviors are dangerous to the horse and handler and destructive to property, as well as being genuine nuisances in the barn, stable and arena.
For a comprehensive list of stereotypies and additional information regarding them, please see article Stereotypies: Bad Habits or Vices? on this site.