Why your dog might bite unexpectedly

Let me start by saying that not all dogs are the same. Each and every dog is an individual and will react differently to certain situations. Certain types of dogs are more reactive and others more laid back, but any dog can bite. Let me shortly give one possible reason.

Dogs, much like us, have reactivity thresholds. When a dog gets stressed, three different hormones get released to help it cope. One of these is called cortisol, and is responsible for an animal's fight or flight responses. When your dog experiences a stressful event, this hormone gets released. Normally, by the time the next stressful event occurs, the cortisol of the previous event has been removed from the system and new cortisol is released. Let's say your dog's reactivity threshold is 10. A first scary event might bring him to number 3 on this scale. Another scary event tomorrow might be 6 on the scale, but still well below 10, so your dog doesn't react.

The problem with cortisol, however, is that it takes the body 5 to 8 hours to totally remove it and to get the dog into a calm state. So if scary events happen over a long time, he will not reach his reactivity level (level 10) as the previous stress hormones have been removed. So, because he never reacts, you consider your dog to be a good dog. One day however, he bites your child who is playing with him. Most people would react, "I don't know what is wrong with him, he has never bitten anybody!

I'll have to have him put down".

On that day, however, your dog might have experienced more stress than usual without you noticing. A cat jumping the fence might have put him at reactivity level 3. When the postman arrived only a few minutes later, more cortisol got released and he reached level 6. Shortly after, your dog saw another dog through the gate, which caused even more stress, bringing him to level 9, with stress hormones flooding though him. Then your child, whom he normally doesn't react to, starts playing with him. His body has not yet had the time to get rid of all the stress hormones, so when your child pulls his ear, his stress level goes over his reactivity threshold and he reacts with a bite to her face.

In this instance the dog is not to blame. This is why behaviourists all over the word strongly disapprove of children interacting with dogs roughly. These kinds of bites can be easily prevented.

For more on dog reactivity, feel free to contact me at george@rehabdogworks.com