An apparatus, a system and methods are disclosed in relation to the configuration and compatibility of a removable delivery section of the apparatus, and delivering a substance via the apparatus to an animal. In an aspect, a hand held apparatus for delivering a substance to an animal includes a removable delivery section including a delivery arrangement adapted to deliver the substance to the animal; and a drive section including a drive arrangement adapted to actuate the delivery arrangement in a coupled condition in which the removable delivery section is coupled to the drive section. The delivery section includes an electronic device adapted to communicate with a control system associated with at least the drive section in the coupled condition, the electronic device being configurable so to be readable by the control system such that the control system is able to identify and operate the removable delivery section.