Horses competing at EA level now must be microchipped. All Thoroughbreds since 2001 must be microchipped.
When horses are sold, they should be scanned for their microchip and checked against the record for ownership. Legislation requires that horses at point of sale be scanned for a microchip. Microchipping is also required is the horse is to be vaccinated for Hendra Virus.
The microchip is a small pellet that is a passive transponder, when an electrical force form a readers is placed over it, it returns information, which is currently what the type of chip is an it's unique number. Newer microchips will also read the horse's body temperature. The microchip sits in the nuchal ligament and is inert.
An aseptic technique is vital for placement of the microchip in the horse. The applicator must be a vet specifically registered for microchipping horses.