Does the hair on your arm, neck or head ever go up involuntarily when you are stressed or overexcited? In humans it is called “goosebumps” but in dogs it’s called “hackles”. The medical term in dogs is piloerection, with pilo meaning hair. Hair doesn’t talk yet it does tell the emotional state of a dog. It is a dog’s way of communicating his feelings. Cats, rats, birds and humans all share the same reaction. Porcupines use this for protection to scare off predators.
A dog’s hackles run down its neck, backbone, shoulder and to the base of its tail. All dogs have hackles, but it is more obvious in certain breeds than others. You can’t see hackling as easily in breeds with longer and fluffier hair, while breeds with short hair tend to show their piloerection more clearly.