You might remember the famously funny scene from ‘Shrek’ where the world’s most grossly misunderstood ogre explains to Donkey, ‘Ogres are like onions… we have layers.’ Well, as it turns out, dogs are remarkably similar. Dogs, just like onions (and ogres!), are often grossly misunderstood beings composed of multiple intricate layers (or ecosystems) that rely on one another in order to thrive fully. And today, I want to spend some time peeling back those layers to show you just how significant they are in ensuring that dogs live a long and prosperous life.
A Dog’s ‘Layers’ Explained
Layer 1: The Physical Shell
The outermost layer is what we see first – the coat, skin and physical appearance.
Much like an onion’s papery exterior, this outer layer is an incredibly fragile one. The slightest trauma could tear, rip and expose the onion to external environments that, if we are not careful, will slowly begin to rot the inner layers.
To ensure we keep a dog protected, we must fully acknowledge that the dog’s skin and hair are essentially the foundation of overall wellness, since the integumentary system is the largest of the dog’s organs, covering the entirety of the body (Scott et al., 2001).
The skin serves as a critical barrier against pathogens, regulates temperature, and provides sensory information about the environment (Marsella and Samuelson, 2009).
As Campbell (2006) notes, “the skin is not merely a passive covering but an active, dynamic organ that reflects the internal health status of the animal.”
Of course, this superficial, albeit delicate layer is merely the tip of the iceberg, what is happening underneath that the eyes cannot so easily see?
Layer 2: The Physiological Systems
Beneath the surface lies an intricate network of bodily systems including (but not limited to) the digestive, nervous, and immune.
Each system doesn’t work in isolation but functions as part of a greater whole. This concept is well established in veterinary science through the understanding of psychoneuroimmunology, which demonstrates the bidirectional communication between the nervous, endocrine and immune systems (Broom and Johnson, 2019).
When we understand this layer, we can understand why any form of trauma to the skin from the external environment can also impact gut health or cause an array of physical symptoms as well. The gut-skin axis, for example, is a well-documented phenomenon where gastrointestinal health directly influences dermatological conditions (Marsella, 2021).
Equally, we can also understand why a skin issue might actually stem from gut health or why stress can manifest as physical symptoms. Research by Dreschel (2010) found that chronic stress in dogs can lead to immunosuppression, gastrointestinal disturbances and dermatological problems.
Both internal and external environments are equally significant when it comes to wellness, since both are interlinked and connected.
Layer 3: The Emotional Core
Dogs experience a rich tapestry of emotions such as joy, fear, anxiety, contentment, love, grief, anger, even anticipation.
The emotional layer is influenced by all other layers, and all other layers are, in turn, influenced by this layer – they are all interconnected.
The scientific evidence for canine emotional complexity is substantial. Bekoff (2007) argues that “dogs possess a sophisticated emotional repertoire that includes primary emotions such as fear and joy, as well as secondary emotions including jealousy, grief, and empathy.”
A dog’s emotional state can impact their physical health, just as physical discomfort can affect their emotional wellbeing. Mills et al. (2020) emphasise that “the relationship between emotional state and physical health in companion animals is bidirectional, with pain influencing behaviour and emotional distress exacerbating physical symptoms.”
They are one and the same.
The limbic system, responsible for emotional processing, is intimately connected with the hypothalamic-pituitary-adrenal (HPA) axis, which regulates stress responses and has profound effects on immune function, digestion and overall health (Palestrini et al., 2005).
Layer 4: The Social Being
Dogs are inherently social creatures with complex relationships, not just with their human families and other family pets but also with their surrounding environment.
This social layer affects how they interact, learn and respond to various situations, which in turn can influence the physical, emotional and physiological systems.
Bradshaw (2011) explains that “dogs have evolved sophisticated social cognition that enables them to navigate complex social environments, and disruption to social bonds can have measurable physiological and psychological consequences.”
Research has shown that positive social interactions increase oxytocin levels in dogs, promoting bonding and reducing stress, whilst social isolation or conflict can elevate cortisol and compromise immune function (Handlin et al., 2011; Rehn et al., 2014).
Layer 5: The Individual Spirit
At the very core, each dog possesses a unique personality and spirit. This might be described as their individual ‘doglyness’ that makes them unapologetically and instinctively who they are.
No two dogs are exactly alike, just as no two onions have identical patterns in their rings. Individual differences in temperament, cognition and behavioural responses are well documented in canine research (Svartberg, 2005).
As Horváth et al. (2007) note, “personality traits in dogs are stable over time and across contexts, reflecting genuine individual differences that must be respected in care and training approaches.”
Therefore, we can begin to appreciate just how special and unique each of our dogs are and how they leave such a big hole in our lives and hearts when they pass on.
Why Understanding These Layers Matters
When we approach dog care with a ‘one-size-fits-all’ mentality, we’re essentially treating all onions as if they’re identical.
But any chef will tell you that different varieties of onions have distinct characteristics, and even onions of the same variety can vary in intensity and flavour.
Take red onions, for example, they are sweet and great for spicy dishes or salads compared to the white variety that are often used for soups and fry-ups.
Similarly, each dog represents its own ecosystem. An ecosystem is a complex interplay of all these layers working together in tandem, communicating to one another in parallel universes, each relying on the other to keep healthy and safe.
This systems-thinking approach aligns with the Five Domains Model of animal welfare (Mellor, 2017), which recognises that welfare emerges from the interaction of nutrition, environment, health, behaviour and mental state.
For example:
A skin condition might not just need topical treatment but could require addressing diet, stress levels and environmental factors. Marsella (2021) found that “successful management of canine atopic dermatitis often requires a multimodal approach addressing nutrition, environmental allergens, stress management, and topical care.”
A behavioural issue might not be solved by training alone but might need a holistic approach that considers physical health and social dynamics. Overall and Dyer (2005) emphasise that “behavioural problems in dogs frequently have underlying medical causes, and comprehensive assessment must include physical health evaluation.”
A gut problem might not be solved with nutrition alone but may require a more in-depth look at how the dog feels emotionally. The brain-gut axis demonstrates that emotional stress can alter gut microbiota composition and function, whilst gastrointestinal discomfort can influence mood and behaviour (Mondo et al., 2020).
The Holistic Approach
This layered complexity is why a holistic approach to dog care is so crucial.
When we care for dogs, we really need to:
- Consider how each layer impacts the others: The interconnectedness of physiological, emotional and social factors means that intervention in one area will inevitably affect others (Broom, 2008).
- Recognise that any changes (regardless of how small) in one area can ripple through all systems and affect the whole being:
“Quality of life in companion animals is determined by the cumulative effect of multiple welfare domains, and improvement in one area can have cascading positive effects.”
McMillan., 2003
- Understand that healing or improvement might need to address multiple layers which may require an entire community of professionals to address. For example The British Veterinary Association (2019) advocates for “integrated, multidisciplinary approaches to companion animal care that bring together veterinary, behavioural, and complementary expertise.”
- Appreciate that each dog’s unique combination of layers requires an individualised approach that is open to experimentation and adaptation as things progress and/or take a step back:
“Treatment protocols must be tailored to individual patient characteristics, circumstances, and responses”
Kaeberlein et al., 2016
Just as an onion reveals its complexity layer by layer, understanding our dogs requires us not only to look at the surface but beyond it too, and appreciate the intricate symphony of systems, emotions and characteristics that make each dog unique and beautiful.
The next time you look at your dog remember the onion analogy.
Take a moment to consider all the layers that make them who they are.
Ask yourself:
- Are you and those responsible for caring for the dog addressing each layer in the care routine?
- Are you and those responsible for caring for the dog truly seeing them as the complex, multi-faceted being that requires a consistent and holistic approach?
Because just like Shrek’s onion, the more layers you peel back, the more you understand fully the reason why dogs are worthy of our admiration, respect and love. But also, the better equipped we all become in providing the best possible service of care they need and deserve.
References
Bekoff, M. (2007) The emotional lives of animals: A leading scientist explores animal joy, sorrow, and empathy—and why they matter. Novato, CA: New World Library.
Bradshaw, J. (2011) In defence of dogs: Why dogs need our understanding. London: Allen Lane.
British Veterinary Association (2019) Integrated approaches to companion animal health and welfare. London: BVA.
Broom, D.M. (2008) ‘Welfare assessment and relevant ethical decisions: Key concepts’, Annual Review of Biomedical Sciences, 10, pp. T79-T90.
Broom, D.M. and Johnson, K.G. (2019) Stress and animal welfare: Key issues in the biology of humans and other animals. 2nd edn. Cham: Springer.
Campbell, K.L. (2006) ‘Small animal dermatology secrets’, Veterinary Clinics of North America: Small Animal Practice, 36(1), pp. 1-2.
Dreschel, N.A. (2010) ‘The effects of fear and anxiety on health and lifespan in pet dogs’, Applied Animal Behaviour Science, 125(3-4), pp. 157-162.
Handlin, L., Hydbring-Sandberg, E., Nilsson, A., Ejdebäck, M., Jansson, A. and Uvnäs-Moberg, K. (2011) ‘Short-term interaction between dogs and their owners: Effects on oxytocin, cortisol, insulin and heart rate—An exploratory study’, Anthrozoös, 24(3), pp. 301-315.
Horváth, Z., Dóka, A. and Miklósi, Á. (2007) ‘Affiliative and disciplinary behaviour of human handlers during play with their dog affects cortisol concentrations in opposite directions’, Hormones and Behavior, 54(1), pp. 107-114.
Kaeberlein, M., Creevy, K.E. and Promislow, D.E.L. (2016) ‘The dog aging project: Translational geroscience in companion animals’, Mammalian Genome, 27(7-8), pp. 279-288.
Marsella, R. (2021) ‘Atopic dermatitis in dogs: Understanding the complexity of pathogenesis’, Veterinary Dermatology, 32(1), pp. 3-e1.
Marsella, R. and Samuelson, D. (2009) ‘Unraveling the skin barrier: A new paradigm for atopic dermatitis and house dust mites’, Veterinary Dermatology, 20(5-6), pp. 533-540.
McMillan, F.D. (2003) ‘A world of hurts—Is pain special?’, Journal of the American Veterinary Medical Association, 223(2), pp. 183-186.
Mellor, D.J. (2017) ‘Operational details of the Five Domains Model and its key applications to the assessment and management of animal welfare’, Animals, 7(8), p. 60.
Mills, D.S., Demontigny-Bédard, I., Gruen, M., Klinck, M.P., McPeake, K.J., Barcelos, A.M., Hewison, L., Van Haevermaet, H., Denenberg, S., Hauser, H., Koch, C., Ballantyne, K., Wilson, C., Mathkari, C.V., Pounder, J., Garcia, E., Darder, P., Fatjó, J. and Levine, E. (2020) ‘Pain and problem behavior in cats and dogs’, Animals, 10(2), p. 318.
Mondo, E., Barone, M., Soverini, M., D’Amico, F., Cocchi, M., Petrulli, C., Mattioli, M., Marliani, G., Candela, M. and Accorsi, P.A. (2020) ‘Gut microbiome structure and adrenocortical activity in dogs with aggressive and phobic behavioral disorders’, Heliyon, 6(1), e03311.
Overall, K.L. and Dyer, D. (2005) ‘Enrichment strategies for laboratory animals from the viewpoint of clinical veterinary behavioral medicine: Emphasis on cats and dogs’, ILAR Journal, 46(2), pp. 202-216.
Palestrini, C., Previde, E.P., Spiezio, C. and Verga, M. (2005) ‘Heart rate and behavioural responses of dogs in the Ainsworth’s Strange Situation: A pilot study’, Applied Animal Behaviour Science, 94(1-2), pp. 75-88.
Rehn, T., Handlin, L., Uvnäs-Moberg, K. and Keeling, L.J. (2014) ‘Dogs’ endocrine and behavioural responses at reunion are affected by how the human initiates contact’, Physiology & Behavior, 124, pp. 45-53.
Scott, D.W., Miller, W.H. and Griffin, C.E. (2001) Muller and Kirk’s small animal dermatology. 6th edn. Philadelphia: W.B. Saunders.
Svartberg, K. (2005) ‘A comparison of behaviour in test and in everyday life: Evidence of three consistent boldness-related personality traits in dogs’, Applied Animal Behaviour Science, 91(1-2), pp. 103-128.
