Why is Doraemon is afraid of mice?

Doraemon, the robotic cat from the popular Japanese manga and anime series, is afraid of mice due to a malfunction that occurred when he was sent back in time to help Nobita. This fear stems from a traumatic incident involving a mouse that gnawed off his ears, leading to his phobia. Consequently, his aversion to mice adds a humorous element to the series, contrasting with his generally helpful and cheerful personality.