Why Do Dogs Shake Their Leg When You Scratch Them?

Sometimes, your canine feels itchy, and you want to rub its skin with the purpose of removing the flea.

However, many people report that their furry friends often kick their legs when doing so, but why do dogs shake their leg when you scratch them?

This article will offer a satisfying answer to this question via the following sections.

To help you comprehend the matter more, I also provide deep insights into the operation of scratch reflex. Let’s get started!

Why Do Dogs Shake Their Leg When You Scratch Them?

why do dogs shake their leg when you scratch them

Dogs shaking their legs when scratched is commonly called the scratch reflex.

As its name suggests, this involuntary response makes your dog’s legs shake unexpectedly when its nerves under the sensitive skin are touched or impacted.

Why do dogs shake their legs when scratched?

This instinct is functional at protecting your dogs from the attack of fleas, ticks, and other harmful animals, which often make a nest and feed on the canine blood.

When these parasites and insects land on its skin and bite it to take the blood, the reflex scheme will be activated to get the irritation away.

That’s why sometimes you will see your dog scratching his ear’s at night.

The same holds true when you brush, scratch, or play with your four-legged companion.

Do dogs like being scratched? The answer varies greatly, depending on its body language and reactions.

For instance, if the pooch is too tired of your daily scratching, it will typically bark loudly and move away.

However, suppose it turns the body over and shows its belly; you may gauge its level of enjoyment and the pup feels comfortable with your act at that time.

Remember not to disregard this involuntary reflex’s importance.

If you see your lovely canine shaking its leg continuously for a while, take it to a reliable clinic because it might feel very itchy and painful due to the bites of parasites.

How Does The Scratch Reflex Work?

How Does The Scratch Reflex Work

The operation of the scratch reflex is quite straightforward to understand. After being scratched or touched, several nerve endings located under the skin will be stimulated.

After this strong stimulation, the nerves will send a signal to the brain.

The brain then receives and analyzes the data before delivering a message back to other body parts, like legs, to kick or shake with the purpose of removing parasites from the skin.

Your light touch is also one of the rationales behind this reflex scheme, and there are some common places on the body, such as the belly, back, ears, flanks, paws, and sides, that easily activate it.

According to the neurophysiologist Sir Charles Sherrington, the dog scratch occurs through four main stages.

The Latency Period

This is regarded as a delayed duration, as the signal has to take time, from being transmitted to the brain via the spinal cord by nerves to traveling back down to the legs and forcing them to shake.

In other words, this is a short period, often lasting a few seconds between the time you scratch your pooch and the time its legs begin to kick.

The Warm-Up Period

The warm-up period is indicative of the leg’s shaking. In the first stage, your canine’s legs start to kick slowly and increase in intensity after shaking a few times.

The more you scratch the skin, the more intense your dog’s leg will kick.

The After Discharge

When you stop scratching your furry friend, its legs continue to make some movements in response before stopping completely. This is called the after-discharge duration.

The brain must take time to receive the signal from the network of nerves when they are no longer stimulated and transmit it back to your canine’s legs, telling them to stop.


This stage only happens when you play with your pet for too long.

After being stimulated for 10-15 minutes, the reflex shows signs of tiring out due to the accumulation of acid lactic within the leg.

Your dog may shake its leg more slowly because it needs to rest and recharge the battery before becoming active again.

Why Does It Usually Work With Belly Scratches?

If you want to receive the strongest reactions from your dog, tickle or play with its belly rubs. This favorite spot is where numerous nerves cluster in high density.

To gain a greater result, you must pinpoint the location of a saddle-shaped region. It is often positioned in the middle of a pooch’s belly that is most receptive to the reflex field.

One theory explaining why this is the most sensitive part of the belly is that it isn’t covered with the full fur, receiving less protection than other body parts and becoming more vulnerable to the attack of pests and parasites.

Is A Dog Scratch Reflex Bad?

Do dogs like being scratched

Normally, the dog scratch reflex doesn’t denote good things. In most cases, it notifies you that your canine is suffering from fleas, ticks, etc.

Yet, it is not very dangerous, unlike the act of your dog biting its tail commonly rendered by internal parasites.

The scratch reflex could be indicative of more problems than that.

Sometimes, this reflex scheme is activated due to the boredom that it doesn’t know what to do instead of playing with its body.

Suppose one day you feel that your four-legged friend is bored instead of running around all day as normal; it could undergo stress, anxiety, and other neurological conditions.

Sickness is also a possible scenario that drains the dog’s energy and exhausts its physique.

As presented above, human petting is a contributor to the scratch reflex. Yet, you’d better not overdo everything.

When your dog displays unpleasant behaviors, like barking or moving away, stop your tickling joke immediately.

Frequently Asked Questions

Which Dog Breeds Are More Prone To The Scratch Reflex?

Every dog has the scratch reflex because it is a common phenomenon and an effective mechanism to prevent the threat of fleas and ticks.

However, the intensity of leg shaking might be different among various breeds.

Some show mild symptoms, while others are more severe, especially in dogs with allergic symptoms and other medical skin conditions.

Do Dogs Like When You Scratch Them And They Shake Their Legs?

The answer depends on your behavior and your dog’s reaction.

As mentioned earlier, if you scratch it too excessively and cause pain, it won’t favor this act, even expressing fear whenever you approach to cuddle it.

On the other hand, suppose you treat everything gently and scratch your puppy in moderation, about once or twice a week; it may enjoy the sensation, stay still in position, and demand you to continue after stopping.

Why Does My Dog Push Me With His Paw When I Pet Him?

The possible reason behind its aggressive reaction is that your dog feels painful and grumpy.

It doesn’t feel comfortable with your scratching; showing negative behaviors is a way of defying.

Another unpopular opinion lies in your pooch’s personality. More specifically, it hates feeling social and interactive with your jokes.

The Bottom Line

This article has solved the mystery: Why do dogs shake their leg when you scratch them?

This is all attributed to the involuntary scratch reflex, a common phenomenon among dog breeds to avert the risks of harmful pests and parasites.

Pay attention to your pet’s reactions to pet them properly.


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Hi I am Mitchell. Dog Growth is a blog about dog caring and training where I share my experiences to my community. Hope you enjoy it!

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