A history of the traceability of animals and animal products.

The author presents a review of the history of traceability as applied to live animals and animal products from antiquity to the 19th Century. The evidence shows that livestock farmers, owners, and those in charge of animal production and health were concerned with traceability from a very early stage. With regard to live animals, individual identification by means of body markings has been practised for over 3,800 years (Code of Hammurabi). Branding with a red-hot iron, with or without a written record of animal characteristics, was employed in most ancient civilisations. This branding technique was principally used on valuable animals, in particular horses, in which case a written record was kept. Individual indelible branding was used on other species over the following centuries, for example, on swans belonging to the Kings of England as early as the 13th Century. Branding for disease control purposes commenced later, prompted by the major epizootics (rinderpest, contagious bovine pleuropneumonia, glanders and rabies). Marking of animals formed part of a series of very pragmatic measures, and the penalties in the event of violation were much more severe than is currently the case. Although modern traceability techniques were not available, our ancestors, as early as the 17th Century, practised indelible branding and strict health certification. Animal products were likewise closely monitored, particularly during the epidemics of human plague during the 14th Century. Some animal products could not be traded internationally unless accompanied by a certificate of origin guaranteeing safety. During the major epizootics of the 18th Century, some contaminated products (meat, hides) were cut up, slashed or covered with lime to indicate that the product was unfit for trade or consumption.

Injectable electronic identification, monitoring, and stimulation systems.

Historically, electronic devices such as pacemakers and neuromuscular stimulators have been surgically implanted into animals and humans. A new class of implants made possible by advances in monolithic electronic design and implant packaging is small enough to be implanted by percutaneous injection through large-gauge hypodermic needles and does not require surgical implantation. Among these, commercially available implants, known as radio frequency identification (RFID) tags, are used for livestock, pet, laboratory animal, and endangered-species identification. The RFID tag is a subminiature glass capsule containing a solenoidal coil and an integrated circuit. Acting as the implanted half of a transcutaneous magnetic link, the RFID tag is powered by and communicates with an extracorporeal magnetic reader. The tag transmits a unique identification code that serves the function of identifying the animal. Millions of RFID tags have been sold since the early 1980s. Based on the success of the RFID tags, research laboratories have developed injectable medical implants, known as micromodules. One type of micromodule, the microstimulator, is designed for use in functional-neuromuscular stimulation. Each microstimulator is uniquely addressable and could comprise one channel of a multichannel functional-neuromuscular stimulation system. Using bidirectional telemetry and commands, from a single extracorporeal transmitter, as many as 256 microstimulators could form the hardware basis for a complex functional-neuromuscular stimulation feedback-control system. Uses include stimulation of paralyzed muscle, therapeutic functional-neuromuscular stimulation, and neuromodulatory functions such as laryngeal stimulation and sleep apnea.