Transponders are inserted into living beings for the purpose of being able to identify them. A transponder is a transmitter-receiver unit with a memory accommodated in a housing. When the antenna belonging to it is radiated from outside, the stored data are sent out by the transmitter unit, so that remote identification of the animals in question can take place. The stored data are unique for each animal through the coding used. Guns provided with a needle-shaped guide are generally used for the insertion of transponders. An opening is made in the skin in one way or another with said needle-shaped guide, following which the guide is inserted further into the body of the animal in question. The transponder is then ejected by the guide, either by means of a bar or by means of fluid pressure.
One method of injection discloses in particular an insertion point for living beings, such as pigs, behind the ear. Although this method of insertion was found to be satisfactory for many animals, it was found that it was unsuitable for animals with moving ears, such as cattle. Unlike pigs, cattle move their ears to a considerable extent, and such animals also have the habit of rubbing their heads along bars of feeder units and the like. These movements cause damage to the transponder and/or force it out of the body. There is also the disadvantage of the transponder being relatively easily accessible.