Page 51 - New Mexico Summer 2022

randomize it a little, the horse won’t anticipate it as much and get worked up.”
“My horses at home are at pasture so this isn’t an issue, but in winter I give them supplemental hay. We don’t have free-choice hay bales, we just feed them twice a day. It’s interesting how they go about life as usual in the morning until they hear me start my car. I go out and start it and let it warm up for a few minutes while I go feed. In the evening, I feed them again. They know the sound of my car, versus my husband’s car, and it isn’t until my car comes in the driveway that they anticipate food—whether it’s at the regular time, or at 2 p.m. if I went home from work for some reason, or as late as 7 p.m. They become eager, thinking I am going to feed them,” says McDonnell.
Random feeding is not recommended for people who don’t understand the reasoning behind it because then they might think it doesn’t matter when they feed their horse. “It’s not an excuse to have unreasonable intervals between feedings.”
If a horse is a stall-walker or weaver or has some other undesirable repetitive behavior, it’s helpful to look at what that horse does during a 24-hour period on video. “That’s easy to do these days. You don’t have to be a trained behaviorist to observe your horse and understand what might be going on with that horse and what might
be setting off those episodes. Your impression
of how much the horse is doing this behavior
is often much greater than it actually is,” she explains. It’s generally only triggered by human activity within the barn.
“Another thing the owner or trainer should do is advocate for that horse and not allow other people to add punishment to the situation, reprimanding the horse for undesired behavior. This just increases the horse’s stress and the state of mind that drives that kind of behavior, even though it might be satisfying to the person who walks down the barn aisle and shouts at
the horse to interrupt the behavior. It makes you feel good, but after you pass by, the horse generally starts up again and the rate increases due to the increased stress,” she says.
It’s best to just ignore it. “You don’t want
to reward it, like feeding them every time they do it, to distract them and make them stop. It’s best to provide no human consequence to what they do, so there is no reinforcement or stress. It’s very hard to do this, however, in a barn with multiple people because they all want to help with that problem horse. At one point we had a student here who drew cartoons and signs to put on the stall door to remind people what not to do with that horse,” says McDonnell.
“At that time, we had some Gypsy Vanners in the barn, and these stocky horses are prone to developing learned repetitive behaviors. When someone came in the barn they started pawing and banging on their stall doors. We
have wooden doors, and it not only made a loud ruckus, but they could actually knock the door crooked on its track, which required a work order to fix. The student made some cute cartoons for various horses with stereotypies, and for the Gypsy Vanners the captions were ‘I’m a-knockin’ but don’t you answer!’ just to remind everyone to walk on by and not even look at that pawing horse. Eventually the barn atmosphere changed and no longer sounded like
The act of cribbing or weaving causes a temporary sedating effect; the horse becomes addicted to his internal chemicals. The horse gets his fix by going through the repetitive behavior, and he craves the endorphins. This explains why many horses will actually stop eating and crib during the middle of a meal.
In experiments, cribbers were given narcotic blocking drugs that neutralize endorphins, and they ceased cribbing as long as the drugs remained in effect. Since the endorphins were no longer released to give the horses a feeling of pleasure, they lost the desire to crib.
The researchers felt that the frustration
of isolation and confinement, or waiting for food, and the horse’s attempt to escape the frustrations were the cause of stereotypic behavior. As the stress increases, his escape attempts (which might at first be kicking
the stall, walking around looking for a way out, pawing or biting the door) become increasingly frantic. Then he discovers that his frenzied actions are rewarded by a feeling of calm and well-being, brought on by release of endorphins. So, he repeats the action. Eventually the behavior becomes a habit pattern even if the stress is alleviated. The stall walker keeps pacing, the weaver keeps bobbing, and the cribber keeps cribbing. The behavior is an addiction, and difficult to halt once it begins.
EQUINE HEALTH
a drum corp. Some of the undesired behaviors will evaporate if these horses get no attention and you don’t reward or punish them,” she says.
“The learning studies and behavior studies that we’ve done over the years make it clear that any sort of attention when an animal is in this situation, where all of their life’s activities depend on someone outside the stall, just reinforces the behavior. In some instances, it can be perceived by the animal as punishment and adds to the stress. This is called a learned helplessness—feeling that nothing you can do can change things. But then the smart horses learn that if they make a big ruckus someone will come and give them attention. Whether it’s yelling at them or feeding them, it drives that behavior as reinforcement,” she explains.
If an owner or trainer is working with a weaver or stall-walker that is doing it so much that it affects that horse’s musculature, it might affect performance in more ways than simply using up energy. There may also be potential injury to feet and legs if they always walk or weave in the same direction or put more stress on one limb, or one side of the limb, than the other.
CRIBBING RESEARCH LED TO UNDERSTANDING STEREOTYPIES
During the 1980’s, a team of scientists at Tufts University School of Veterinary Medicine in Massachusetts, discovered why horses crib and why this behavior is so persistent. It was found that horses given morphine showed an increase
in stereotypic behavior such as cribbing. Sweet feed in the diet also increased these activities; very palatable feeds have been shown to increase release of endorphins in the horse, raising the pain threshold. Whenever an animal or human
is stressed and engages in some type of repetitive activity as an outlet for pent-up energy, chemicals called endorphins are released in the brain. The constant activity triggers endorphin release.
Thus, when a horse starts a continual repetitive action such as stall walking, weaving or cribbing in response to confinement or stress, he may keep up the habit even when
not confined or stressed, because he finds that repeating the pattern triggers release of calming morphine-like proteins (called opioids) which suppress pain and create a pleasurable sensation. Horses seem to relax and be “spaced out” after a cribbing or weaving session.
The act of cribbing or weaving causes a temporary sedating effect; the horse becomes addicted to his internal chemicals.
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