A horse is considered an adult at age 4, but may continue to grow until about 7.
 

Horses are measured in hands (a hand is 4 inches).  A horse is anything over 14.2hh (hands high).  Anything under 14.2hh is a pony.
 

Horses usually live to be 20-25 years old.  The oldest horse on record lived to be 62.
 

A full grown horse that weighs 1,000 pounds contains approximately 13.2 gallons of blood, and has 175 bones.
 

A horse’s hoof grows a little less than a half-inch per month.
 

Given complete freedom, horses spend about 16 hours a day feeding.
 

A horse produces about 9 tons of manure in a year.
 

A horse can not vomit.  It has special one-way valves that prevent food in its stomach from being thrown up.
 

Horses lie down for a total of two hours a day.  They spend about nineteen and a quarter hours alert, two hours drowsy but alert, two hours in light sleep, and three-quarters of an hour in deep sleep.  Their sleeping cycles are broken down into small segments, sometimes only lasting 5 minutes.  Adult female horses spend even less time lying down than males and juveniles.
 

A stallion can smell a mare in heat up to a half mile away.
 

The horse’s eye is one of the biggest in the animal kingdom.  It can see about 340 degrees of the 360 around it, the blind spots are the first 4-5 feet directly in front of its nose, and directly behind the tail.