HorseRacingQA.com

The most expensive racehorse ever was the 2000 Kentucky Derby winner, Fusaichi Pegasus, who raced just five times for trainer Neil Drysdale, but nonetheless accrued nearly £1 million in prize money and was sold to Coolmore Stud for £53.7 million at the end of his three-year-old campaign. The sale proved excellent business for his original owner, Fusao Sekiguchi, who bought him for just over £3 million as a yearling, but less so for Coolmore Stud. The son of Mr. Prospector proved a less-than-stellar acquisition and was eventually pensioned off stallion duty, as a 23-year-old, in 2020.

Interesting, John Magnier and his Coolmore Stud associates Michael Tabor and Derrick Smith also hold the record for the most expensive horse ever sold at public auction, a two-year-old son of leading US sire Forestry, from the family of Storm Cat, called The Green Monkey. At the Fasig-Tipton Calder Sale in January, 2006, The Green Monkey was knocked down to his new owners for £12 million and put into training with Todd Pletcher. He did not see a racecourse until the following September and, when he did, was placed just once in minor company before being retired from racing in February, 2008. He subsequently stood at Hartley/De Renzo Thoroughbreds in Ocala, Florida, but was equally unsuccessful as a stallion.

Of course, during a race, each horse carries its own, unique colours – the jockeys of horses in the same ownership wear distinguishing caps – so it is easy enough to tell one from another. However, for security purposes, it is important that a horse can be identified on its arrival at the racecourse stables. All horses, regardless of their date of birth, must nowadays be microchipped and the unique microchip number must be registered on the Central Equine Database (CED), which is maintained by the Department for Environment, Food & Rural Affairs (DEFRA).

Telling one racehorse from another should therefore be as simple as scanning microchips on entry but, occasionally, a microchip cannot be read, so all horses must also, legally, have an identification document, or ‘passport’. Along with its unique microchip number, a horse’s passport also includes details of its colour and marking, such that it can be used to identify the horse, if need be. Horses racing for the first time may have their passports checked but, thereafter, identification by scanning the microchip is usually all that is required. Ultimately, if a horse cannot be identified, by one means or another, it cannot run in a race.

The performance of a racehorse depends, in no small part, on the capacity of its blood to deliver oxygen to, and remove carbon dioxide from, its tissues. Consequently, it stands to reason that a mature racehorse, which has higher blood volume and, hence, higher oxygen-carrying capacity is capable of running faster than an immature horse. However, respiration is not the whole story; the age at which a horse reaches peak performance is also influenced by its pedigree, soundness, temperament and training regime, among many other factors.

Healthy horses have a natural lifespan of 25 years or more, on average, and do not stop growing until they are around five years old. However, Flat-bred horses typically begin their racing career as two-year-olds and those with breeding potential are often retired to stud at the end of their three-year-old campaigns. Thus, while they would typically reach peak performance between four and five years, if kept in training, they never have the chance to do so.

By contrast, many National Hunt-bred horses are robust, strong, late-maturing types, a.k.a. ‘store’ horses. Almost invariably, male horses are gelded, or castrated, and have no breeding value, so are allowed to mature before being put into training at the age of three, four or more. Such horse typically reach peak performance between seven and ten years, depending on the age they enter training and the discipline(s) in which they compete.