Stress and Digestion

Alexa Linton, Equine Sport Therapist, BSc. Kin

It is not at all uncommon to meet a stressed horse. Often, we don’t even realize that this is the case, as there are virtually no outward symptoms. A stressed horse may seem lethargic, unwilling under saddle or uninterested in their food. A more acute and recognizable stress response would be snorting, wide eyes, tension, obvious agitation and fast, panicked movements. However, even low-grade stress has the potential to wreak havoc on the body systems if it lasts for a long period of time. During the body’s natural response to any stressor, “flight or fight”, there is a rapid and dramatic shift in the body systems as compared to the relaxed state. Today we will be focusing on the negative effect of stress on the digestive tract, although the immune, circulatory, nervous and hormonal systems can all be affected on a large scale.

The digestive tract of the horse is one of the largest sources of stress in the horse owner. Perhaps it is because of the extreme sensitivity of this group of organs, but if things go wrong it usually begins here. Most obviously colic and gastric ulceration, but also laminitis and founder can all originate in the digestive tract. Every one of these conditions sends shivers down the horse owner’s spine and can have detrimental and even fatal effects on our horses.

It goes without saying that we want to keep the digestive tract running smoothly. So far we have looked at the effects of acid-alkaline balance and toxicity, as well as the addition of probiotics, essential fatty acids and electrolytes to maintain balance, but how about a less easily controlled variable, namely stress? Stress, as many of us are aware, can cause a multitude of reactions in the body, some noticeable and others all but invisible. Every one of us has heard the term “silent killer” applied to high blood pressure, a disease caused largely by stress, which is all but invisible to the person affected and those around them. In theory, stress is a very important response, alerting us to change in our environment, causing our body to switch into overdrive to complete a necessary task. It is a response developed purely to ensure our survival.

The physiological explanation for the stress response is very simple; essentially, when the body goes into a “flight or fight” response due to a stressor, it steers all energy into the most necessary processes, namely, all processes required for physical exertion. There is a major influx of blood and neural firing to the muscles, as well as the rapid release of adrenalin and other hormones. The focus is therefore removed from equally crucial processes such as digestion. But the same stress, when maintained over a longer period of time can have devastating effects on the body.

Not only is the body physically exhausted, but inevitably there is increased tension, nervous energy, rapid and shallow breathing, and an above normal heart rate. But it is often the organs that are not considered essential during the stress response that suffer the most, those of the digestive tract, immune system, and the elimination system. In the digestive system, lack of blood and neural response means a lower rate of breakdown and absorption, ultimately leading to discomfort, gas, inflammation and possible toxicity.

For horses, as prey animals, the “flight or fight” response is critical for survival, and is highly developed and intensely sensitive. In situations where there is a change in environment, food, owners, weather, or exercise program, there is often stress. As well, stress may also be present if your horse is not able to move around regularly in a field or large paddock, does not have a chance to play or interact, or if the horses or people in their environment tend to be stressed or agitated.

It is very important to recognize that your state of mind has a huge impact on your horse. As herd animals they thrive in a congruent atmosphere, one where the action matches the state of mind or emotion. For example, if you are highly stressed but pretend that you are doing great, your horse may be very irritated by your incongruency. Imagine a bear walking by a herd of horses with a full belly and then with an empty belly. His path may have been identical, but the reaction of the herd would have shifted dramatically. Although they grazed passively the first walk-by, you can bet they were not sticking around to be eaten the second time. Acknowledge that you are feeling stressed and your horse will tend to relax, as now your inner emotional state is congruent with your outward state.

Horses can also become stressed in the presence of threatening stimuli, as we have all found out. However, most horses will gradually become desensitized to the stressful stimulus if it is introduced on a regular basis. It is when this stress response is prolonged, that there is reason to worry. For example, horses with a busy competition season will often show signs of chronic stress. The constant changing of environment and long trailering rides as well as the pressure of competition, stress of the owner and the overall exertion on the body can cause a great deal of stress over a prolonged period of time. Studies have shown that the combination of intense training, reduction in turnout, and lack of a constant supply of roughage can actually increase the production of stomach acid. It is no wonder that 60% of horses used in competition show signs of gastric ulceration.

Paying attention to your horse is the best way to tell if they are experiencing stress. Be sure to watch for changes in energy level, weight, mood and tension in their body. Check out their environment from the eyes of a horse. Make sure it as close to that of a wild horse as possible, with lots of movement, play and interaction with you, constant access to roughage, in a safe space away from predators and other hazards. As you are the leader, it is important to develop a relationship where your horse learns to trust you in stressful situations, understanding that you will not bring them into a situation which is dangerous. If a field or group turnout is not possible, it is even more necessary to allow time to play and interact with your horse. Allow this to be stress relieving for both of you by letting go of expectations. Just have fun! Spend the day giving your horse a massage or walking together on the trails.

If you and your horse are competing heavily it is crucial that the environment around your horse is as stable as possible, including your own stress level. Try to provide the same hay on a continuous basis throughout the day, stick to a regular feeding schedule and make sure to spend quality grazing and walking time with your horse. It may even be helpful to use calming herbs such as Chamomile, Lavender Essential Oil, or Rescue Remedy to further reduce stress levels. There are many excellent natural products on the market that can help your horse to find inner peace. For more information on helping your horse relax contact your local Equine Health Professional.

Happy relaxing!