Emotional Health in Pets: Relieving Stress and Anxiety

Animals may experience emotional health problems similarly to how a human may struggle with stress or anxiety. Pets’ emotional health may present in different ways; after all, they can’t communicate directly to their owners about what’s going on in their heads! Understanding what emotional health looks like in pets as well as what nutritional strategies may support pets’ emotional health, however, can help pet parents support their pets throughout their lives.

Defining Emotional Health Problems for Pets

Stress is broadly defined as conditions where an environmental demand exceeds the natural regulatory capacity of an organism. This may occur in situations characterized by unpredictability and uncontrollability. Stressors are unpredictable stimuli that result from a loss of control or that lead to a disruption of homeostasis (a balanced state). Homeostasis is a self-regulating process by which biological systems maintain stability while adjusting to changing external conditions._1,2 Anxiety, on the other hand, results from a complex interaction of environment, conditioning (prior exposures), genetics, and neurologic adaptation that occurs over time.₃ Anxiety or fear may be appropriate in some cases; however, repeated overreactions to harmless situations indicates a failure to habituate to normal stimuli.₄

What Types of Stress Do Pets Experience?

Pets can have physiological stress such as that experienced when dealing with trauma, veterinary treatments or surgeries, or when experiencing a disease condition. They can also experience stress stemming from a psychological origin rather than physical one (referred to as psychogenic stress) which may result from social causes such as introduction to new people or environments. Pets also experience physiological stress from nonsocial causes such as exposure to noise, altered light/dark balance, smells, and cage or crate confinement either at home or in a veterinary hospital or boarding facility. A compromise in normal mobility can also be a source of chronic stress for pets due to pain or simply lack of movement.

Some of the stressors pets experience can be reduced through modifying their environment by limiting noise, avoiding routine disruption, facilitating calm handling, and supporting mobility. It is important to note, though, that some stress is unavoidable in veterinary care such as when using restraint needed for veterinary procedures or treatments.₃

What Type of Anxiety Do Pets Experience?

Anxiety is similar to psychogenic stress. It is often described as apprehension related to a future situation, and it is not related to a specific threatening object. Anxiety can result from prior negative experiences. Recognized disorders of anxiety in pets include separation anxiety and noise phobias.₆

Stress Regulation in the Body

Physiological responses to stress are regulated through either rapid or slow mechanisms.  The sympatho-adreno-medullary axis (SAM) manages immediate responses to stress through the release of catecholamines from adrenergic nerves of the adrenal medulla. This response occurs within seconds of a stimulus. The hypothalamic-pituitary-adrenal axis (HPA) alternatively releases hormones from the hypothalamus which causes release of corticotrophin-releasing hormone that will stimulate the posterior pituitary to release ACTH. ACTH enters the blood and acts on the zona fasciculata of the adrenal cortex to release glucocorticoids (cortisol). This slower response may occur over hours, days, or weeks.

Other hormones in the body that are involved in stress regulation include dopamine, oxytocin, endogenous opiates, and endocannabinoids._3,6 The body may habituate to a stressor, with the magnitude of the response declining over time. Alternatively, the body may become sensitized – which could result in a heightened response to that stressful stimulus. Excessive heightened responses to stressors will result in pathology or disease states over time.₉

Disease states in pets related to stress and anxiety include:

• Immune suppression; increased susceptibility to infections_10-12
• Gastrointestinal disease_{13, 14}
• Cutaneous disease₁₅
• Delayed wound healing_{16, 17}
• Alterations in pain perception₁₈

Minimizing Risk and Treating Stress and Anxiety in Pets

Efforts to reduce stress and anxiety in pets may include non-pharmacologic methods such as altering the environment to provide privacy or hiding areas, calming music, protecting normal routines and sleep, or providing supplemental natural pheromones. Pharmacologic interventions may include drugs or supplements aimed to modify stress responses or reduce anxiety levels. Nutrient support through diet or supplementation is an intervention that can support the body’s stress regulatory mechanisms and help it naturally manage stress.

Supplements and Functional Ingredients for Stress and Anxiety in Pets

Supplements and functional foods may serve to influence regulation of stress and anxiety in the body. Some examples include:_{19, 20}

• Alpha-lactalbumin: bovine milk derivative; source of tryptophan
• Apoaequorin: is a calcium-binding protein; reduces calcium related neuronal cell death
• L-Theanine: AA found in tea plants; increase GABA, serotonin
• Medium chain triglycerides: fuel source for brain; refractory seizures
• Docosahexaenoic acid (omega-3 fish oil): development of neural and retinal tissues
• S-Adenosylmethionine: methyl donor, antioxidant; synthesis and inactivation of neurotransmitters
• L-carnitine: fatty acid metabolism; improves mitochondrial cell functions
• α-Casozepine: structurally similar to γ-aminobutyric acid; an amino acid that functions as an inhibitory (calming) neurotransmitter in the brain.

Nutrient Support for Stress and Anxiety in Pets

Providing key nutrients may ensure all building blocks are present for important metabolic pathways involved in stress and anxiety management. Some key nutrients and active ingredients found in supplements include:

• Phytocannabinoids: support homeostasis or balance, supply a source of omega-3 and omega-6 fatty acids₁₉
• Probiotics/Prebiotics: modulate physiological systems, including gastrointestinal function, immunity, and metabolism₂₀
• Glandular tissues: support homeostatic mechanisms for many glands in the body including the adrenal, pituitary, and pineal gland, brain nervous tissues, gut, and brain-gut axis; provide a source of peptides, enzymes, lipids, steroids, and low dose hormones₂₁
• Vitamins: niacin, pyridoxine, folate, thiamine, and cobalamin₂₂
• Minerals: magnesium, calcium, potassium, selenium, zinc, copper, and manganese_23-26
• Melatonin: Epicenter of circadian rhythms, synchronization of biological rhythms, anti-inflammatory, neuroprotective, and anti-nociceptive_{27, 28}

Managing Stress in Pets: A Multi-modal Approach

Reducing stress in pets should include evaluation of the pet’s general health status, environment, routine, exercise, and nutrition, including all foods and supplements. Veterinary input should be sought to review the pet’s lifestyle, routine, current disease conditions, medications, diet, and supplements.  Reduction in stress and anxiety can be achieved by utilizing multiple different interventional modalities.  Optimizing the pet’s environment and nutrition with a high-quality diet and nutrient support through supplements may help ensure that all key metabolites are present when needed, as well as promote and maintain a normal, healthy stress response.

References

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