This is a highly specific form of protective aggression. That is the mother that will not allow others near her litter.Less typically, it is sometimes used to describe the aggression of a mother towards her pups, which does not involve long dominance downs or shaking of the pups, or any prolonged harshness, beating, etc. Discipline is brief, sharp and scary. It usually involves a vocalization +/- a grab of the back of the neck and is directly associated with the maladaptive behavior of the pup.