It is a zone around the animal that is the animal's safe area. For example, a horse may allow its owner to brush it while a stranger can get no closer than 20 feet before the horse moves away. Your position in the flight zone controls the speed or direction of the animal's movement and the distance entered. Most animals will display some type of signal to show if they are fearful, aggressive, or content. These signals can be ear or tail position, raised back hair, bared teeth, pawing the ground or snorting.
Several situations can make livestock difficult to handle.
Animals with young will display strong maternal instinct and resist attempts to become separated. Young should be kept with the parents whenever possible. Animals handled roughly will likely remember the experience and be more likely to overreact to being handled. Many animals also develop a strong territorial attachment to their pens or pastures. Animals can become quite upset if separated.