Methods of Identification for Horses

Equine Section Department of Animal Sciences

In today's competitive world of equine sports, proper identification has become a top priority. Thorough and effective identification ensures that the horse being bought, sold, raced or bred is indeed the horse claimed.

The Jockey Club was the first organization in the United States to set up an accurate identification system for horses. In the early 1900s, the thoroughbred racing industry was having problems with "ringers" running under assumed names. A ringer is a falsely identified horse entered in a race below its class, giving it an almost certain chance to win. Today there are many methods used to identify a horse, including markings, cowlicks, chestnuts, tattooing, freeze branding, blood typing, and microchip identification.

Body Markings

Chestnuts—Chestnuts or night eyes are horny, irregular growths on the inside of the horse's legs. On the front legs, they are just above the knee. On the rear legs, they are toward the back of the hock. Chestnuts are like human fingerprints because no two are alike, and they don't change in size or shape throughout the horse's adult life.

Cowlicks—Cowlicks are permanent hair whorls which cannot be brushed or clipped out. They are located mainly on the forehead and neck.

Dimples—Dimples are permanent indentations in the muscle under the skin. They are usually located at the point of the shoulder or in the neck muscles.

Others—White or black patches on the body, scars, and firing marks on the legs are also useful markings for identifying horses.

Head Markings

Star—A solid white mark on the forehead. The shape may range from oval to diamond to a narrow vertical, diagonal, or horizontal star.

Stripe—A white mark starting at eye level or below and ending on or above the upper lip. The size and shape of a stripe may vary widely and must be described in detail as to width, length, and its relationship (whether it is connected or unconnected) to a star.

Snip—A white or beige mark over the muzzle between the nostrils.

Blaze—A wide patch of white extending down the face and covering the full width of the nasal bones.

Bald face—A wide white marking which extends beyond both eyes and nostrils.

Horse Heads

Leg Markings

Coronet—A white marking covering the coronet band.

Pastern—A white marking from the coronet to the pastern.

Ankle—A white marking from the coronet to the fetlock.

Half-stocking—A white marking from the coronet to the middle of the cannon.

Stocking—A white marking from the coronet to the knee.

Stocking Plus—A white marking like the stocking, but the white extends onto the knee or hock.

White on knee or hock—A separate white mark on the knee or hock.

White spots—White spots on the front of the coronet band or on the heel.

Distal spots—Dark spots on a white coronet band.

Horse Feet


Bay—Body color ranging from tan through red to reddish brown; mane and tail black; usually black legs.

Black—Body color true black without light areas; mane and tail black.

Blue Roan—More or less uniform mixture of white with black hairs on the body, but usually darker on head and lower legs; can have a few red hairs in mixture.

Brown—Body color brown or black with light areas at muzzle, eyes, flank, and inside legs; mane and tail black.

Buckskin—Body color yellowish or gold; mane and tail black; usually black on lower legs. Buckskins usually do not have dorsal stripes.

Chestnut—Body color dark red or brownish-red; mane and tail usually dark red or brownish-red, but may be flaxen.

Dun—Body color yellowish or gold; mane and tail may be black, brown, red, yellow, white, or mixed; usually has dorsal stripe, zebra stripes on legs, and transverse stripes over withers.

Gray—Mixture of white with any colored hairs; often born solid-colored or almost solid-colored and get lighter with age, or more white hairs appear.

Grullo—Body color smoky or mouse-colored (not a mixture of black and white hairs, but each hair mouse-colored); mane and tail black; usually black on lower legs. Usually has dorsal stripe.

Paint—The two most common paint color patterns are tobiano and overo. The tobiano horse will usually have head markings like a solid-colored horse; legs may be white, and body markings are often regular and distinct, being oval or round patterns. The overo horse will often have a bald face, at least one dark-colored leg, and body markings that are usually irregular, scattered, or splashy white (these markings that do not cross the back between the withers and tail).

Palomino—Body color golden yellow; mane and tail white. Palominos do not have a dorsal stripe.

Red Dun—A form of dun with body color yellowish or beige; mane, tail, and dorsal stripe are red.

Red Roan—More or less uniform mixture of white with red hairs on the body, but usually darker on head and lower legs; can have red, black, or flaxen mane and/or tail.

White—A true white horse is born white and remains white throughout its life. A white horse has snow-white hair, pink skin, and brown, hazel, or blue eyes.


The tattoo consists of a letter which corresponds to the year the horse was born and a number which matches the registration number of the horse. The tattoo may be placed in several areas, but the upper lip is the most common site. The actual tattoo instrument consists of a chrome-plated brass block which contains a needle pattern with a varying number of needles, depending on the particular number or letter. The needle pattern was developed over several years until a specific pattern was obtained that could not be easily altered.

Before the tattoo is applied, the horse is carefully scrutinized with regards to color, marking, cowlicks, chestnuts, and other easily identifiable traits. Once the identity of the horse is assured, the mucous membrane on the upper lip of the horse is exposed using a lip clamp. The area is cleaned with alcohol, and the proper digits are placed in the tattoo gun. The gun is then dipped in an antiseptic (i.e., Zephiran chloride) and applied to the lip. Finally, ink is rubbed into the perforations.

Lip tattooing was perfected by the Thoroughbred Racing Protective Bureau (TRPB). The Jockey Club uses this method of identification to guarantee the identity of every racing horse at a track which is a member of the Thoroughbred Racing Association (TRA).

Freeze Brand

Freeze branding uses an unalterable system of angular symbols developed by Dr. Keith Farrell, a veterinary medical officer with the USDA. As with tattooing, the first symbol represents the year the horse was born followed by the registration number. The brand is most commonly applied to an area approximately 2" x 7" midway on the neck, underneath the mane.

The identity of the horse is double-checked before the brand is applied. Copper stamps or marking rods are cooled in liquid nitrogen or dry ice. An area under the mane is shaved and washed with 95% alcohol which aids in conducting the intense cold. The copper stamp is applied to the animal's skin for 10 to 20 seconds. An indentation is left in the skin immediately after the brand is applied. Some swelling may occur in the first few days; however, after two months, a distinct and permanent mark remains. The intense cold kills the pigment-producing cells, called melanocytes, leaving an area of pigment-free skin. On dark-colored animals, the hair grows back white, and on white animals an area with no hair results.

Freeze branding has many advantages over fire branding. A freeze brand produces minimal changes in the hide, is more distinct and legible, does not produce an open wound, and is relatively painless.

Freeze branding is used by the Arabian Registry to identify purebred Arabians. An "A" is placed in the first position of the system of marks to indicate "Arabian."

Blood Typing

Although markings, tattooing, and freeze branding are effective in differentiating individual horses, blood typing has been developed over recent years and is an equally effective alternative. Serologists test for the 16 most common blood antigens and serum proteins. The combinations seem limitless as there are some 125 billion possible blood types in horses. Blood typing is used by the Jockey Club, the American Quarter Horse Association, the Arabian Horse Registry and others.

Microchip Identification

To deter thieves from stealing horses and to aid in recovery of stolen horses, a new method of identifying horses has emerged over the past few years. The implantation of a small microchip the size of a grain of rice containing the horse's registration number or identification number can assist in identifying a horse if by chance it turns up stolen.

The veterinarian uses a specially designed needle and syringe to implant the microchip. A local anesthetic is administered about midway down the horse's neck just below the crest. The chip is then inserted into the ligament in the neck, using the custom syringe. The chip is actually lodged about an inch underneath the skin's surface. It is equipped with a non-migratory tip to ensure that it stays in place.

What separates the microchip identification method from other methods is that it cannot be altered. The chip is read by using a hand-held scanner, similar to those used in grocery stores. Many slaughterhouses and brand inspectors have scanners for identification in several states.

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