This testing device is designed to allow the user to verify whether an animal is taken, without having to remove the trap. It also allows the user to ensure, during the placing of the trap that the state of the constituents of the trap, such as the battery or the element, are capable of igniting. The device consists of a warning lamp (7) and an electric contact (8), which may be of the push button type and associated wiring. The cabling forms a series connection between the battery (5), the warning lamp, the contact and the internal filament (1) of the pyrotechnic charge. The push button may be replaced by a magnet operated reed switch, which allows the contact to be established. When the circuit is completed by the contact, instead of the animal contact, the current in the circuit is not sufficient to set off the charge.