Three
All horses are considered to have a "birthday" on January 1st, regardless of what was the actual date of birth of each horse. This can be a serious matter in the Kentucky Derby, where only "three year old" horses are eligible to run. If a horse was born on Dec. 31st, it is considered one year older than a horse born on Jan. 1st, and would therefore only be eligible to race in the Derby when it was chronologically less than two and a half years old.
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Three years old.
All horses in the Northern hemisphere are considered to have a "birthday" on January 1st, regardless of what was the actual date of birth of each horse. This can be a serious matter in the Kentucky Derby, where only "three year old" horses are eligible to run. If a horse was born on Dec. 31st, it is considered one year older than a horse born on Jan. 1st, and would therefore only be eligible to race in the Derby when it was chronologically less than two and a half years old. However, most foals are born between January and May, with the advantage being a few extra months' growth, which at that age can be significant.
The Kentucky Derby is a race for Thoroughbreds.
European horses can enter the Kentucky Derby.
The first year that a woman entered a horse in the Kentucky Derby was 1904. Her name was Laska Durnell. Her horse, Elwood, won the Derby that year.
The Kentucky Derby is only for three years olds. They cannot be older or younger.
The Kentucky Derby
The Kentucky Derby did not begin until 1875.
Giacomo won the Kentucky Derby in 2005.
The Kentucky Derby is a Thoroughbred horse racing event.
The first gray horse to win the Kentucky Derby was Determine in 1954.
You will not see a Paint horse in the Kentucky Derby. The Derby is for Thoroughbreds only. A Paint is a spotted horse with Quarter Horse and Thoroughbred bloodlines.
Horse 'Secretariat' won the Derby in 1973.
If you are talking about the Kentucky Derby, the horse was Jet Pilot.