HERE’S AN EASY way to make a few bucks before the Kentucky Derby: Bet your friends that every horse on the track is a Capricorn. While they’re scrambling to look up all those equine birthdays, drink their juleps.
Then make your case: Under a byzantine rule created more than a century ago, every racehorse has the same birthdate, January 1. Born on May 27? Overridden. On paper, every horse on the track Saturday is 3 years, 4 months, and 6 days old.
Which is weird, because in nature, horse birthdays actually tend to fall in the spring and summer. (“I’m going to blame a man for this,” Barbara Murphy, an equine science professor at the University College Dublin, says of the universal racehorse birthday, “because it was someone who didn’t understand the breeding cycle of female horses.”) See, horses are long-day breeders, meaning they become fertile as spring arrives and the days lengthen. (People are “continuous breeders,” a nice way of saying they get knocked up all year long.) A mare can get preggers between April and October, and because the gestation period is 11 months, she gives birth between March and August.
The distribution for racehorses, however, looks significantly different.
Racehorse foals tend to be born between January and April, earlier than the March–August timeframe you’d see in the wild.
That’s because the birthday rule—established in 1851 by the British Jockey Club to make age grouping “simple”—dramatically increases demand for horses born as soon after the New Year as possible. Think about it. Say it’s January, and you’re looking at buying one of two yearlings. The first was born last January, so he’s a full year old. Look at that glossy coat! Those rippling muscles! The other was born in July, so chronologically he’s just six months old, all knobby knees and fluffy tail. It would be like putting a toddler in first grade and expecting him to be able to read.
The result of this bogus birthday? Breeders do everything they can to make sure foals are born as early in the next year as possible, including triggering mares’ fertility hormones early in the year. And they do it by recreating the sun.
Recreating the Sun
When light hits receptors at the back of the retina, an electrical impulse activates that acts, as Murphy puts it, as “the master pacemaker of the biological clock.” That clock sends a signal to the pineal gland, which reduces the melatonin being produced and triggers a horse’s springtime hormones. Breeders know exactly how much light a stabled thoroughbred needs: A mare in a 12×12 stall needs 8 extra hours of light post-sunset from a 200-watt bulb.
In 1947, Cambridge researcher John Burkhardt found that putting mares under artificial light created the same effect as natural daylight. So owners flip the switch in mid-November or December, subjecting mares to about 6 hours more of “day” than the 9 or so they’d normally get at that time of year. “If you fly into Lexington at night before breeding season, it’s like flying to a different planet,” Murphy says. “You can see all the barns lit up like spaceships.”
Then, at the start of the breeding season in February, boom! The mares are ready to rumble a month or two early, which means their babies arrive a month or two earlier, making them that much “older” than their non-light-shifted peers. (If you screw up the timing and your horse is born December 31? Bad luck. The next day, your horse is considered a yearling.) And indeed, since the understanding of the effect of this kind of seasonal jet lag took hold in the 1950s, the real birthdays of Kentucky Derby winner (and especially of Triple Crown winners) have fallen earlier and earlier in the year.
But keeping all your mares in specifically lit barns has downsides. Breeders pay higher electricity bills, sure, but many horses do better in pastures where they can walk and graze freely; confined to stalls, they can develop health issues and behavioral problems. So in 2013, Murphy’s company, Equilume, came out with a blue-light mask. The headpiece straps on like a fly mask and has a cup under one eye. Once the mask is activated, a short wavelength blue light in that cup lights up automatically each night. “The suppression of melatonin is susceptible to blue light, which is kind of like the light at dawn and dusk,” says Murphy.
Equilume’s light is similar to the blue LED in your phones that keeps you awake. (Binge-watch Game of Thrones or fire off a few emails before tucking in and your brains dials down melatonin.) Does that mean there are a lot of sleep-deprived mares stumbling all over Kentucky? Not really.
Research has shown the masks don’t impact a horse’s ability to rest, probably because horses have different sleep cycles than humans—they sleep just 2.5 hours a day in 15 minute bursts.
Not only can masked horses live in pastures full-time, but the masks stimulate some mares that don’t respond to indoor lighting methods. (The otherworldly effect of glowing barns is not totally lost, however. Stuart Brown, a vet and racehorse breeding consultant in Kentucky, was walking his dogs one night when he saw blue lights bobbing in the dark. UFOs? Police lights on the public road behind his property? Nah, just cyborg horses: Brown had forgotten that he had put Equilume masks on his four broodmares.)
Hacking the Odds
Gamblers don’t seem to care much about the horse hacking. “I’ve never looked at it, I’ve never thought about it, I’ve never considered it,” says Stu Kirschenbaum, a handicapper, regular better, and lifelong racing fan. “Never in my entire life has it ever once come up in conversation with the people I go to the track with or talk to about the races.”
So why do breeders spend so much time and money manipulating exactly when horses have their babies? By the time thoroughbreds compete in the Derby at age 3, most differences between horses born a few months apart have evened out. But even the smallest advantage helps. “There’s no doubt in a sales setting that horses foaled later just don’t have the size and presence of their counterparts,” Brown says. (After all, the last three Triple Crown winners were born in February, placing them on the older side compared to their peers.)
Indeed, Todd Pletcher, a leading trainer with two horses in this year’s Derby (Destin, born April 16, and Outwork, born March 8), draws a hard line when looking at young horses. “I will buy late May foals but not June,” he wrote in an email. “When looking at yearlings I will look at the foaling date and keep it in mind. Perhaps a May foal will seem undersized or a January foal will seem very mature.” Some concessions must be made for those younger horses in training, too. At Payton Training Center run by Pletcher’s father, for example, they won’t breeze (a term for letting a horse work at a moderate speed) a May-born horse as soon as his older peers.
And while light therapy is all about winning races, it also helps maximize profits for mare owners and stud income for elite stallions. Before the therapy became widespread, thoroughbred foaling rates were around 50 percent. Today, lighting systems, hormones, and tech that detects exactly when a mare is ovulating push that to more than 80. Now that more mares can get pregnant and breeders see higher success, stallions are busier getting busy, bringing stud fees in the tens of thousands.
But why not drop all the tinkering and change the universal birthday to, say, March 1, which would align with the natural breeding cycle? Air-kissers of the world would be … inconvenienced. “The absurd thing is I’ve been told we would have to alter the whole social season,” William “Twink” Allen, renowned equine fertility researcher, says. Horses running for the roses in May would trend a few months younger and might not be mature enough to run, pushing the Derby back, thus interfering with tennis season, rowing season, and everything else that fills the calendars of the elite.
Until that happens (it probably won’t), there’s another way to make a little money this Saturday. You could look at a horse’s track record, the weather conditions, the trainer’s background, and the horse’s position in the starting gate. You could put your money on the favorite. You could pick the jockey with the loudest silks. Or you could try a truthier astrological bet, and when the winner crosses the finish line, wager your pals that he’s either an Aquarius or a Pisces. Maybe an Aries. Statistically, the track is full of them; one is likely to be standing in the winners’ circle.
Source: thx wired