The checks made to ensure the right horses run at tracks

Horses can be identified in two ways when they get to the racecourse: via their passports or by scanning the microchip inserted partway down their neck when young.

Before entering the secure stables area all horses are scanned by an official to identify the microchip. Following this the horses are assigned a box for the day.

The only additional checks are carried out by the judge in the paddock before the race. This is a basic assessment of the horse, checking it is the correct colour, sex and has the right equipment for racing. It could not discern the difference between two similar-looking horses.

Following the race, the majority of winners plus any additional horses requested by the stewards – normally those who have run markedly above or below form – are taken to provide a blood or urine sample at the secure sampling unit. They are escorted there by an official.

When they reach the unit they have their microchip scanned for identification. No other horses in the race are checked.