Thoroughbred Development Timeline

Foal

Birth — about 4 to 6 months old

A thoroughbred is a foal from birth until it is weaned from its dam, generally between four and six months of age. The foaling season runs from January through May, and every thoroughbred shares an official January 1 birthday for record-keeping.

• arrow_rightFoaling season: January through May. The earlier in the year a foal arrives, the more physical maturity it carries against its 'classmates' come sale time.
• arrow_rightLives in the field with its dam — nursing, growing, learning to handle and to be handled.
• arrow_rightRegistered with The Jockey Club, with the foaling year recorded; from January 1 of the following year the horse is officially a yearling, regardless of actual birth date.

Weanling

About 4 to 12 months old

A foal becomes a weanling once it is separated from its dam — generally at four to six months — and stays a weanling until January 1, when it officially becomes a yearling.

• arrow_rightSeparated from the dam and turned out with other weanlings, which is also how they learn social structure.
• arrow_rightLight handling: leading, picking up feet, being bathed, standing for the farrier and vet. The work that makes the eventual breaking job easier.
• arrow_rightFall mixed sales (November) include weanlings, the first chance to buy or sell at auction.

Yearling

About 12 to 24 months old (calendar age)

A yearling is a thoroughbred in the calendar year after the year it was born. The major yearling sales run in September, and most yearlings are broken in the fall — making the yearling year the inflection point between farm animal and racehorse-in-training.

• arrow_rightContinues growing and being handled, but not yet ridden.
• arrow_rightSeptember yearling sales are the largest thoroughbred auctions of the year — Keeneland, Saratoga, OBS — where most racehorses change hands.
• arrow_rightBy late summer or early fall the buyers are picking sale horses apart with their veterinarians; by mid-fall the horses are heading to breaking barns.

Breaking

About 18 to 22 months old — the fall of the yearling year

Breaking is the foundation of a racehorse's education: teaching the yearling to accept tack, a saddle, and a rider, and to be ridden at the walk, trot, and gallop. Done patiently, the work pays off for the rest of the horse's career.

• arrow_rightFirst saddle, first rider, first time turning in a controlled circle under tack — staged over weeks, not days.
• arrow_rightYearlings learn to gallop in company with other young horses, ponied alongside a steady older horse.
• arrow_rightGate schooling begins in earnest: walking into a starting gate, standing quietly, leaving cleanly.
• arrow_rightA well-broken horse moves through every later stage faster, sounder, and with a better mind on it. A poorly broken horse can carry problems for the rest of its career.

Two-Year-Old in Training

Officially 2 — but really about 22 to 30 months old

A two-year-old in training has been broken and is now being conditioned: longer gallops, faster works, gate schooling, and — for sale horses — preparation for the spring 2YO sales and their under-tack shows.

• arrow_rightBuilds fitness: routine gallops most mornings, breezes (timed fast works) every week or two.
• arrow_rightSpring two-year-olds in training sales — March, April, June — are the biggest events of the year for sale horses, each preceded by an under-tack show where the horse breezes an eighth or quarter mile for buyers and clockers.
• arrow_rightSale-bound horses are pointed at the under-tack breeze; a fast, clean breeze can multiply the hammer price. A slow or labored one can sink it.
• arrow_rightTrack-bound horses get gate approval, debut as maidens, and start their racing careers — often in the summer or fall.

Racehorse

2 to 5 years old (and sometimes much longer)

A racehorse runs its way up the class ladder — from maiden to claiming, allowance, condition, and stakes races — while a trainer manages soundness, fitness, and where the horse is placed each time out.

• arrow_rightMost horses start in the maiden ranks. A horse 'breaks its maiden' the first time it wins.
• arrow_rightFrom there, the class ladder runs through claiming, allowance optional claiming, and condition races (N1X, N2X, N3X) — each step up in difficulty and purse.
• arrow_rightStakes races are the top tier; graded stakes (Grade 1, 2, 3) are the most prestigious, and even placing in one earns the boldface 'black type' that lasts a lifetime in sales catalogs.
• arrow_rightDay to day, the trainer's job is placing the horse in the right race, keeping it sound, and getting it to the gate ready to run.

Beyond Racing

Typically 5 years and up

When a racing career ends, a thoroughbred can move on as a stallion, broodmare, retired companion, or second-career sport horse — and a stakes-quality colt or filly is often worth more in retirement than it was on the track.

• arrow_rightSuccessful colts retire to stud and earn a stud fee per mare bred — the biggest money in the sport is on the breeding side.
• arrow_rightFillies and mares may join broodmare bands, where their foals can inherit their class and family.
• arrow_rightGeldings and horses without breeding value typically race longer and then move to second careers — show, eventing, trail, or simply a long retirement.
• arrow_rightScat Daddy — broken and trained early in his career while Mario was an assistant to JJ Pletcher — went on to become a prominent racehorse and influential stallion.