Over the course of the last decade, there’s been ample evidence
to support the idea that chronic stress plays a contributing role in a variety
of medical conditions in humans. It may come as no surprise that researchers
have similarly determined that long-term stress can be a factor in the medical
and compulsive disorders of companion animals. Conditions such as feline lower
urinary tract disease, inflammatory bowel syndrome, obesity, gastric dilatation
volvulus (bloat), noise phobias and separation anxiety have all been found to
have a chronic stress component in both dogs and cats (Luescher, 2003). Even so,
compared to humans, relatively little research has been published regarding
stress and its effects on companion animals.
Some presume that the effects of stress on dogs and cats are not
much different than those on other non-human animals. But, it appears that
they’d be wrong.
In the mammalian world, dogs and cats are unique due to the
bonds they share with humans, marked by their social interactions and the human
homes in which they commonly reside.
As dogs and cats have gradually changed from living in natural
settings to co-habitating with humans, one might expect that they would have
fewer stressors than their outdoor ancestors. However, the evidence seems to
contradict this assumption. Some veterinarians argue that, even though
environmental stress is lower for today’s companion animals (i.e., less risk of
predation, starvation, etc.), overall stress levels are actually higher.
Furthermore, current sources of stress - such as boarding, veterinarian
examinations, long-term confinement in a crate, boredom, habitual inactivity and
even the sounds of modern life - are ones against which dogs and cats may not
have well-developed defenses and are often unavoidable.
Stress has been eloquently described as “the sum of all
nonspecific biological phenomena caused by adverse conditions or influences ...
include[ing] physical, chemical, and/or emotional factors to which an individual
fails to make satisfactory adaption and that cause physiological tensions that
may contribute to disease” (Campbell et al, 2004). Bodies manage stress through
the autonomic nervous system and the endocrine system (referred to as the
“hypothalamic-pituitary-adrenal axis”). In general, the response of the
autonomic nervous system is very rapid and specific, whereas the endocrine
system adjusts more gradually and is broader in its effect.
In order to mount an adequate stress response, both the
autonomic nervous system and the endocrine system require nutrients that can
only be obtained through dietary intake. For example, the endocrine messengers (norepinephrine,
acetylcholine, and cortisol) are synthesized by the body. However, in order for
the body to create these messengers, it needs to obtain tyrosine, choline and
acetate, as well as cholesterol and acetate … all from dietary sources.
Synthesis of these endocrine messengers is also dependent upon ingesting
nutrients such as zinc, copper and manganese, as well as significant amounts of
vitamin C. In the autonomic nervous system, signal transmission is made possible by
electrical activity in the nerve cells. Fueling this activity requires dietary
intake of sodium, calcium and potassium. All of these elements are vital for
normal nervous and endocrine system responses to stress.
As a holistic pet food formulator, I know that the way the body
responds to stress and chronic disease might have predisposing nutritional
factors, such as a nutrient deficiency, imbalance, or toxicity. A good
formulator must know whether or not supplementation of a given nutrient can help
a companion animal manage stress effectively.
In spite of how well you care for your dog or cat, it is still
likely that they will encounter daily stressors. While unavoidable, it is
possible to minimize the effects through a combination of exercise, nutrition
and holistic treatments.
Substances like valerian, chamomile and inositol can help to
soothe the jangled nerves of dogs. Pheromone diffusers and sprays are effective
stress reducers for both dogs (D.A.P) and cats (Feliway). If your budget is tight, you can do pet massage at home to help relieve tension. To develop a program of stress reduction
that’s uniquely suited to your companion animal’s needs, consider enlisting the
help of an alternative-medicine or holistic veterinarian.
Perhaps most importantly, keep in mind that providing proper
nutrition is vital for helping companion animals deal with stress and lead long,
healthy and happy lives. In addition to feeding a high quality diet, feeding them a daily supplement is a simple way to ensure sufficient nutrients to
maintain a healthy endocrine and nervous system, in turn helping to cope with
any stress your pet encounters.
Thank you for all you do to make the world a better place for companion animals. Each and every one of you has my sincerest wishes for holiday full of joy, and a wonderful new year of health!
Dr. Jane Bicks
References
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Luescher, A.U. 2003. Diagnosis and management of compulsive disorders in dogs and cats. Vet. Clin. North Am. Small Anim. Pract. 33:253-267.
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