Trancing rabbits is the action of placing rabbits on their back to induce a paralysis known as Tonic Immobility (TI). The action is also known as: the immobility response, hypnosis or freeze response.
Rabbits can be put into TI if they are physically restrained on their backs with their head flexed against their neck. The signs of a tranced rabbit includes closed eyes, shallow fast breathing and relaxed limbs. Rabbits act this way when put into this position because they are a prey species. It is a last defence against a predator. The rabbit will lie motionless, thereby giving the impression of being already dead and encouraging the predator to release it’s grip and hopefully presenting an opportunity for escape.
Studies have proven that rabbits in TI state show an increased heart rare and respiratory rate, with elevated plasma corticosterone levels (which indicates fear induced stress). Contrary to popular belief, rabbits in a state of TI are not relaxed, hypnotized or insensitive to pain. Research has further shown that rabbits who have been put in a TI state show adversely affected behaviour. rabbits tend to hid away more, grooms itself more, and shows less inclination to explore. The more often a TI state in induced and the longer the length of time the rabbit is ‘tranced’ for, the worse the effects.
In the UK most rabbit experts, welfare organisations and vets caution against the use of TI or recommend it is only used as a last resort; for example a nervous rabbit needs examining and other means of restraint has failed, or it is required instead of a anaesthetic.