What do the letters AA after a horse's name stand for?

Eagle-eyed racing fans will have recently noticed a handful of runners in Britain and Ireland carrying the letters AA in addition to their country suffix.

Though there are only four such horses on the Racing Post database, they include the Henry de Bromhead-trained Falco De Candale AA, a five-year-old Walk In The Park gelding who was a neck second in a Cork bumper earlier this month.

There is also the Willie Mullins-trained K'chou Du Pecos AA, another five-year-old Walk In The Park gelding who was fourth behind the blue-blooded Neptune - a Galileo brother to Irish 1,000 Guineas heroine Nightime - on debut at Leopardstown in late December.

The letters AA after a racehorse's name stand for Anglo-Arabian - a separate breed to thoroughbreds which is the result of various crosses between thoroughbreds, Arabian and Anglo-Arabian horses.

To qualify as Anglo-Arabian or AA, at least 12.5 per cent of a horse's genetic make-up must be Arabian. Previously, a percentage of between 12.5 and 25 per cent saw horses fall under the category of Anglo-Arabe de Complement or AC.

"K'chou Du Pecos is very similar to a thoroughbred," says Patrick Mullins, who rode the son of Walk In The Park at Leopardstown.

"Like the AQPS horses, you wouldn't pick him out, he looks the same as the rest of them. We've had many AQPS horses but not a lot of Anglo-Arabians. They're very successful in France and if they're successful there I can't see why they wouldn't be successful over here."

Both Falco De Candale and K'chou Du Pecos were conceived when Walk In The Park stood for a lowly fee at Haras des Granges in France, and the pair proved especially attractive at the 2017 store sales following the emergence of the sire's sons Min and Douvan.

Noel Meade parted with £75,000 for Falco De Candale at the Goffs UK Spring Store Sale, while Aiden Murphy went to €140,000 for K'chou Du Pecos at the Tattersalls Ireland Derby Sale. Both were consigned by Peter Vaughan's Moanmore Stables.

"There's not a lot of difference between Anglo-Arabians and thoroughbreds," says Vaughan. "The two I sold were both beautiful-looking horses. I've also a full-brother to K'chou Du Pecos heading to the Tattersalls Ireland Derby Sale this year."

K'chou Du Pecos boasts one of racing's household names on his page, with his granddam Chouravia an unraced half-sister to Garde Champetre, with whom Enda Bolger regularly plundered the cross-country races at Cheltenham.

While something of a rarity at present, Anglo-Arabians already have some notable supporters, as Falco De Candale runs in the maroon and white of Gigginstown House Stud, while K'chou Du Pecos carries the distinguished all-navy silks of Sue Magnier.

Aiden Murphy parted with €140,000 for the imposing K'chou Du Pecos at the 2017 Tattersalls Ireland Derby SaleCredit: Tattersalls Ireland

What's more, JP McManus is the registered owner of Sully D'Oc AA. The five-year-old son of Konig Turf is in training with Anthony Honeyball having previously been trained in France by Guy Cherel, for whom he won four of his seven races.

County Kildare trainer John Carr can take credit for being the first to get the ball rolling in Ireland with Dark Du Tabert AA, a son of obscure stallion Baloo Du Camp whose dam Garvina is a full-sister to Harvis, a five-time winner for Toby Balding in Britain after he was recruited from France.

While Anglo-Arabians are yet to get on the scoreboard in Britain or Ireland, they have registered some notable results elsewhere, with Monpilou a Grade 3 hurdle winner at Auteuil and Aragorn D'Alalia winning the Listed Prix Le Parisien hurdle at the same course in 2017, despite being the only Anglo-Arabian in the 16-runner field.

Anglo-Arabian horses to put in your tracker:

Falco De Candale AA

K'chou Du Pecos AA

Sully D'Oc AA