Saturday is the Kentucky Derby, when the fastest of the fast will compete. Most race horses start at age 2 and can race until the mandatory retirement age of 12-15 that most tracks set.

Between 70-80 percent of registered Thoroughbreds race at some point during their lives.

What happens to the Thoroughbreds who did not reach elite racing status? They may find careers as sport horses or as general family horses. If they retire from racing while still healthy, chances are better that they will find a good home.

There is a dark side to horse racing, which we will explore another time.

This blog is a tale of three Thoroughbreds that I am familiar with.

BooBoo’s registered name is Intrepid Air, born in 1994 in New York. He ran in four races and won some, but not enough to keep him in racing. In 1999 he was retired, gelded, and sent to a barn in Pennsylvania to rest and to be retrained as a sport horse. There he met high school student Jessica Sheidy, who liked him a lot.

Jessica convinced her parents that this was the horse for her, and she nicknamed him "BooBoo." Racing was all BooBoo knew when Jessica bought him.

Together they gained experience in riding on the flat and jumping. They showed hunter/jumper, dressage, and cross country. BooBoo grew to love trail riding.

They shared many good times, but have also faced major challenges. At age 11, the horse developed an upper hind end injury. The cause was never determined but was suspected to be due to rough horseplay in the field with his friends.

He spent five days in The University of Pennsylvania Veterinary Hospital, and was later confined to his stall. With care and patience, Jessica started BooBoo walking, progressed to light exercise, and was gradually able to ride him again.

During college and graduate school, Jessica was tempted to sell BooBoo, as money and time were tight, but she always found a way to keep him. At present, Jessica and BooBoo are working on dressage, and will continue to jump as long as he is healthy and seems to enjoy it. Her goal is to retire him in his old age to her back yard.

Opie was also a racehorse, born in Michigan with the name Creative Career and called "Toby." He started in six races, but did not place. Evidently, he was not in much of a hurry.

Most recently he raced at the troubled Pinnacle Race Track in Huron Township. Since the racing thing wasn’t working out so well, Toby retired at age 4.

He was purchased by a woman who planned to buy low, retrain him as a sport horse, and sell higher. This plan went off course when life became too busy. She listed him for sale on craigslist.com, where Halley Sissom, who had been searching for a horse, happened to see him.

Upon meeting the young gelding, Halley was immediately impressed by his mellow attitude. She re-named him “Optimus Prime,” or “Opie” for short. He is tall and lean, and coming along well learning his new job.

Jumping was certainly something foreign to him. At first Opie clamored over or through small obstacles in a most undignified manner. Halley, with her faithful Dad replacing knocked over jump poles again and again, patiently worked with Opie as he learned to control his body and master a new skill. Halley is training him to be an eventing horse, and he is well on his way.

Joli Vent was born in 1998 in Florida. He had 23 racing starts and some wins. He was sold a few times, working his way down from early bigger races in Florida and New York, ending his racing career in 2002 at another troubled Michigan track, Great Lakes Downs. This track closed in 2008.

Joli was purchased for a song by a woman who retrained him as a sport horse. That woman then sold him to us after three months off the track. With capable training and regular work, Joli progressed nicely.

In 2004 he suffered a series of health problems stemming from an adverse vaccination reaction and nearly died. He was reduced to a skeletal state over the next weeks, refusing to eat. Just as it seemed he was truly kicking the bucket, he recovered his appetite and slowly improved.

His recovery was marred by several bouts of colic. The veterinarian attending him during the first and worst colic episode missed the jugular vein in his neck while attempting to inject pain medicine. After several redirections of the needle, the caustic medication was injected outside the vein, resulting in a large abcess, extending from Joli’s jaw to his chest, draining up to two cups of pus per day, for 11 weeks (ick!).

This eventually healed, but the jugular vein does not work on that side — blood from his head finds collateral circulation back to his heart. After a long and bumpy road to recovery, Joli now is fine at age 13.

He has given riding lessons, participated in pony parties and has been successfully shown in a variety of disciplines. Joli is much loved by his rider, 14-year-old Cecilia Lundberg, who began riding him when she was 4 years old, a little fly on his back, wearing pink cowgirl boots.

She plans to continue to ride, jump and show him as long as his health allows, at which point he will be semi-retired to recreational riding.

Do these horses look rather similar to you? For a clue as to why this may be, see last week’s column.

Each horse has its story. For many, the most important part may be that which is never known.

Have a Thoroughbred without papers and looking for his true identity? Most Thoroughbreds who have raced have tattoos inside their upper lip to permanently identify them: one letter followed by five numbers. The letter indicates the year of birth: "A" started in 1971 and again in 1997.

As the horse ages, the tattoo may become blurry and difficult to read. If you need help identifying a Thoroughbred, the Jockey Club may be able to help.

Kathy Lundberg is the owner of Scio Church Stables. Email her at scs@sciochurchstables.com.