A radio frequency identification, RFID, transponder, comprising: a radio frequency, RF, transceiver; and memory in communication with the RF transceiver, the memory storing data retrievable by a scanner via the RF transceiver, the memory being programmed according to ISO 11784/11785 code structures and comprising: (i) read-only memory comprising a unique identification, UID, code unique to the transponder, wherein the RFID transponder is programmed to transmit the UID code upon receiving a UID-read signal by the transponder; (ii) field-programmable memory comprising a default RFID telegram comprising a sequence of data continuously transmitted by the transponder automatically upon activation of the transponder by the scanner, the default RFID telegram comprising data identifying an animal associated with the transponder; and (iii) field-programmable memory comprising an encrypted signature generated by encrypting a signature comprising the default RFID telegram and the UID code using a public-private key encryption scheme, the RFID transponder being programmed to transmit the encrypted signature upon receipt of a memory-read signal by the transponder, wherein the RFID transponder is compliant with ISO 11784/11785 code structures. a radio frequency, RF, transceiver; and memory in communication with the RF transceiver, the memory storing data retrievable by a scanner via the RF transceiver, the memory being programmed according to ISO 11784/11785 code structures and comprising: (i) read-only memory comprising a unique identification, UID, code unique to the transponder, wherein the RFID transponder is programmed to transmit the UID code upon receiving a UID-read signal by the transponder; (ii) field-programmable memory comprising a default RFID telegram comprising a sequence of data continuously transmitted by the transponder automatically upon activation of the transponder by the scanner, the default RFID telegram comprising data identifying an animal associated with the transponder; and (iii) field-programmable memory comprising an encrypted signature generated by encrypting a signature comprising the default RFID telegram and the UID code using a public-private key encryption scheme, the RFID transponder being programmed to transmit the encrypted signature upon receipt of a memory-read signal by the transponder, (i) read-only memory comprising a unique identification, UID, code unique to the transponder, wherein the RFID transponder is programmed to transmit the UID code upon receiving a UID-read signal by the transponder; (ii) field-programmable memory comprising a default RFID telegram comprising a sequence of data continuously transmitted by the transponder automatically upon activation of the transponder by the scanner, the default RFID telegram comprising data identifying an animal associated with the transponder; and (iii) field-programmable memory comprising an encrypted signature generated by encrypting a signature comprising the default RFID telegram and the UID code using a public-private key encryption scheme, the RFID transponder being programmed to transmit the encrypted signature upon receipt of a memory-read signal by the transponder, wherein the RFID transponder is compliant with ISO 11784/11785 code structures.