These may include panting, pacing, or whining in addition to the tail-chasing. Dogs can show many signs of mental illnesses, ...

Sometimes, cats can start chasing their tail because it’s painful or itchy, in which case you might notice their body ...

On a base level, it's normal for dogs to chase their tails, explains Alt. Tail-chasing that occurs every once in a while and a dog can be easily distracted from is "not really an issue," she says.