The birth of a new foal is one of the most exciting aspects of horse ownership. Eleven months of waiting, and finally your new foal is here. He's got his dam's colouring and his sire's markings, but how tall will he be? A variety of methods exist to estimate a foal's adult height, but many owners opt for a string test. The string test is not difficult to perform, and is a fairly accurate indicator of adult height.
Catch the foal and fit it with a halter and lead rope. Enlist a helper to hold the foal or tie it to a secure hitching post if it will stand calmly without an assistant.
Hold a thick piece of string in one hand, and place the string directly over the centre of the foal's knee. If you don't have string handy, a piece of flexible twine from an open hay bale is an acceptable substitute.
Pull the string down along the cannon bone with the other hand, stopping at the coronet. Draw a line across the string at this junction with a permanent marker.
Lay the string on a flat surface, and measure it from the end to the marker spot. This measurement, in inches, will give you an approximate adult height for your foal. For example, if the measurement is 15-1/2 inches, then the foal should mature around 15.2 hands tall.
Horses are measured in increments called hands, with each hand being four inches tall. To measure your horse in hands, divide the total number of inches by four. If your horse is 64 inches tall, then he stands 16 hands tall. If the horse falls between whole numbers, then he is measured with a corresponding fraction. A horse measuring 61 inches tall is 15.1 hands tall, or 15 hands, 1 inch tall.
Don't tie the foal up if he has not been trained to stand tied. You and the foal could both be injured if he is frightened and pulls back.