Dogs like humans share many similarities, especially when it comes to their internal systems. One of the most critical systems they possess is the Autonomic Nervous System (ANS), an important part of the Central Nervous System. This system has two main parts: the Parasympathetic Nervous System (PNS) and the Sympathetic Nervous System (SNS). Grasping the functions of these two systems is key to understanding your dog's behaviour, especially in situations that provoke stress or relaxation.
The Autonomic Nervous System: An Overview
The ANS regulates involuntary functions in your dog's body, such as heart rate, digestion, respiratory rate, and reflexes. It operates without conscious thought, allowing dogs to navigate their daily lives with ease. When your dog approaches a squirrel or hears the doorbell, the ANS responds instantaneously, enabling rapid shifts in behavior and bodily function.
The Parasympathetic Nervous System (PNS)
The PNS system plays a crucial role in helping your dog relax and recover from daily stresses. The PNS is like being on auto pilot it controls for example, walking, breathing, being at rest, digestion the things that we take for granted and which happen automatically without thinking about it. Whereas the SNS elevates heart rate, the PNS helps to slow down the heart rate following a stressful encounter. It calms a dog down and allows the dog to be more receptive to learning. A dog in PNS is in a good place to allow the immune system and body to repair itself.
The Sympathetic Nervous System (SNS)
The SNS kicks in when for example, feeling nervous, fearful, anxious, or stressed. A dog has no control over SNS.
The body automatically releases cortisol as the hormone adrenaline into the bloodstream which in turn gets the dog ready for action. It increases blood flow to muscles, blood pressure, increases heart rate, digestion stops, slows the breathing, frees up fatty acids (a source of fuel) and sugar in blood which causes pupils to dilate.
When a dog is in SNS they can take on the following behaviours: fight or flight mode, fooling around (licking or jumping up), freezing on the spot and very rarely, fainting.
Let’s investigate these further:
Fight Mode
When a dog perceives a threat they may try to bite, air snapping and lunging forward.
Flight Mode
Flight mode is characterized by your dog’s instinct to escape, they will try and run away from the perceived threat.
Fooling Around
Some dogs respond to stress by acting in a playful manner. The dog may often display this as jumping up, pawing at you, wrapping paws around you, licking, over excitement, appear overconfident and play bows. This can be observed incorrectly by the person as this dog loves me or is happy.
Freeze Response
In the freeze response, the dog presents as motionless as if frozen to the spot (shutdown), almost seen as giving in and acceptance. The dog does not move or respond and is overwhelmed.
Fainting
Although rare a dog can faint due to extreme stress.
The Impact of the SNS on Canine Behaviour in the Grooming Environment
When in SNS the dog’s survival instincts kick in and the dog presents with high vigilance and anxiety and becomes more reactive to small stimuli. The increase in adrenaline and cortisol affects the brain and the dog’s ability to think before reacting. The result is a dog that may overreact to situations that it finds itself in. All dogs will react differently to a given situation, just as humans would, to a perceived threat.
A dog in SNS is in a bad place the immune system doesn’t function as effectively as it should due to high levels of adrenaline. Long-term this can lead to poor health of the dog, lowered immune system and muscle atrophy.
Ideally, we do not want a dog to be in SNS whilst they are being groomed as it makes it dangerous for the dog and the groomer. It is important to know when a dog has crossed over from the PNS to SNS as it will impact on grooming during and future grooming sessions. Any grooming experience that occurs whilst the dog is in SNS will be seen as a negative experience for the dog and potentially banked as a bad experience for subsequent grooms. A dog in SNS is unable to learn or form positive memories. Therefore, if we are trying to change a dog’s behaviour to grooming, we need to ensure that the dog remains in PNS in order for any desensitisation methods to be successful. A dog in SNS can go from arousal to aggressive in a matter of moments.
If we observe a dog in SNS then changing our grooming approach is vital. We need to ensure that we are aware of how we are interacting with the dog. How we touch, bath, dry, comb, brush and clip, as these could easily overload the dog’s nervous system pushing them into SNS as observed below:
Another important factor is a dog’s skin sensitivity. Adolescents, for example, can become very touch sensitive. Fisher (2019)
Stress in dogs of any age also impacts on the sensitivity of the skin, making any contact more uncomfortable, including brushing, clipping, bathing and drying…
…any contact with the dog whilst bathing, drying, brushing etc should be done slowly. Quick movements, rubbing, brushing, drying quickly can stimulate the central nervous system making the dog livelier, whereas slowing the movement down will help to calm him. Williamson (2021) Chapter 5 – The Autonomic Nervous System.
When a dog is in SNS they are unable to take on new information, unable to learn they are unable to rationalise what is occurring. Their mind is overthinking and makes quick decisions and dogs are unable to process the information with which they are faced.
Having a dog in the salon in SNS would not be conducive to the dog being able to learn and associate positive experiences, instead it would more likely be associating whatever is happening as a negative experience. The result would be that its next visit to the groomers would be more stressful for the dog as it would already have a negative experience banked.
How Dog Owners Can Help Support Their Dogs ANS
Supporting your dogs PNS and SNS can enhance your dog's quality of life. Here are some ways to help:
Creating a Calm Environment
Create a safe space for your dog away from distractions and providing a designated quiet area.
Implement Positive Reinforcement Training
Use positive reinforcement techniques to build your dog's confidence and reduce anxiety.
Regular Exercise
Regular physical activity is great for recovering from stress.
Use Calming Sounds
Consider playing soft music in your dog's space to help dogs relax, reducing anxiety.
Final Thoughts
Understanding how the Autonomic Nervous System works in dogs and how the PNS and SNS influence behaviour, you can better appreciate your dog's reactions to various situations such as grooming.
At Vanity Fur VIP we advocate for your dog to have regular puppy introductions and grooming sessions this is to ensure that your dog does not get overwhelmed with the grooming experience and that they remain in PNS for a more positive grooming experience.
I hope you found this useful!
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Written by Melanie Braddock @ Vanity Fur VIP Dog Grooming
Taking the Grrr Out of Grooming Your Dogs - Approved Groomer
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