Your complete guide to horse breeds, care, and riding from around the world
Raven SiJohn

Raven SiJohn

  • Joined: 02/11/2013
  • Articles: 215

How big is a hand?

Equines are measured in units. Which unit of measure is used depends on the association doing the registration. Some registries use inches to determine size, since it is easier than trying to convert to hands. Other registries record measurements in hands.


A hand is four inches. The story behind this unit of measurement is that a farmer went to measure his favorite horse. Not having a device to measure with, he used the only thing he knew would be consistent: the palm of his hand. Since then, the hand has been the unit of measure for equines.





Abbreviations for hands


The letters HH or hh after the numbers stand for Hands High. The single letter H or H may be used, standing just for "hands".

Parts of a hand are given after the whole unit, following a decimal. 10.2 hands (can also be read as just Ten-two) means ten hands and two more inches. (4 inches x 10 hands equals 40 inches, plus two additional inches, so 10.2 is 42 inches tall). 10.3 would be 10 hands and 3 inches, forty-three (43) inches. There is no such thing as 10 hands 4 inches, as 4 inches would be an additional hand. However, even fractions of an inch can be listed, such as 10.3 ¾ hh. (Ten hands, 3 ¾" inches, or Ten-three and three-quarters: just ¼" shy of a full 11 hands.)

Some examples of hand measurements


3.3 hands - 15 inches at the withers, the smallest horse ever documented. Too Small! But, this animal reportedly only lived to be two years old (just short of what anyone would call mature).


4.2 hands - 18 inches.  A few Miniature foals are only 18 inches high at birth.


6 hands - 24 inches. There have been a few Miniature Horses reported at this height (short?) in recent years.


6.1 hands - 25 inches - unverified report of the smallest known mature Miniature Donkey


6.2 hands- 26 inches - the height of the smallest known breeding Miniature donkeys (in the USA) and also the height of the smallest known mule in the world (General Grant).


7 hands - 28 inches. A few Miniature donkeys this small, difficult for females in pregnancy and birthing. Animals this small prized in some circles, but conformation tends to suffer.  Either malproportioned in some cases, or very tiny with weak bone.


7.2 - 30 inches. Was once being debated as the cut-off point for breeding size in Miniature donkeys (no plans by ADMS to do this)


8 hands - 32 inches. Miniature size for horse, donkey or mule. Good average for Miniature Donkey height.


9 hands - 36 inches - breakover point from Miniature to Small standard for donkeys with no pedigree (Maximum height 36") . Still miniature height for mules.


9.2 hands - 38 inches. Maximum allowable height for Miniature donkeys with BOTH parents registered as Miniature. Still classified as Oversized in MDR.


10 hands - 40 inches. Breakover for small standard to Standard donkeys. (Still Miniature height for mules)


11 hands - 44 inches. Standard donkeys in this height range. Common height for most of the Plains zebras (Grants, Damaraland, Chapmans)


12 hands - 48 inches. The breakover from Standard to Large Standard in donkeys


12.2 hands - 50 inches. The breakover from Miniature to Saddle Mules.


13 hands  - 52 inches - large Standard donkeys. Considered Pony height in horse breeds. Top end height for zebras, only Grevy's species usually get this tall.


13.2 hands - 54 inches - breakover from Large Standard to Mammoth height in Jennets


14 hands -  56 inches - breakover point from Large Standard to Mammoth for Jacks and Geldings


14.2 - 58 inches - in horses considered the line between Pony (under 14.2) and horse height. Typical size of many Mustangs, although a recent infusion of outside blood in some herds produces larger animals now.


15 hands - 60 inches - typical for many saddle horse breeds, mules, and reaching the top end for Mammoth height. About average height for Arabians and some Gaited breeds.


16 hands - 64 inches. Getting pretty large for a donkey, but a few jacks reported close to this height. Typical range for saddle mules, draft horses, and many saddle horse breeds.


17 hands - 68 inches. Extremely large for a donkey, they tend to "fall apart" in conformation at this height. Commonly seen in some Draft horse breeds, Warmbloods, and a few saddle mules.


18 hands - 72 inches. A few specimens this tall, but unusual in all but a few breeds, mainly Warmblood or Drafters.


19 hands - 76 inches! (6 foot, 4" at the withers). Taller than most men!


19.1 hands - 77 inches high, 6 foot 5 inches at the withers. The height of the tallest Mule in the World, according to the Guinness Book of World Records. Apollo, (b 1977, in TN) is listed with teammate Anak at 18.3. (75 inches)


20 hands - 80 inches.


21 hands -  84 inches


21.2 ½ hands - 86 ½ inches at the withers. Tallest horse ever documented, a Shire gelding named Sampson (aka Mammoth with good reason!) measured in 1850 and listed in the Guinness Book of World Records.



The information provided in this article is courtesy of the American Donkey and Mule Society and is (c) by the ADMS.  Permission is granted to copy for educational purposes (ie school papers, 4-H work, general education websites, fairs, expos) provided that the work is sited as provided coutesy of the American Donkey and Mule Society.  (c) 2001, 2002, 2003, 2004


 

Anatomy of the Horse Foot



A horse's hoof is composed of the wall, sole and frog. The wall is simply that part of the hoof that is visible when the horse is standing. It covers the front and sides of the third phalanx, or coffin bone. The wall is made up of the toe (front), quarters (sides) and heel.


 



When the foot is lifted off the ground, the sole and frog are visible, as well as the bars of the wall and the collateral grooves (Figure 1).


Figure 1 - The wall, bars and frog are the weight-bearing structures of the foot.


Structures of the horse foot



The wall of the hoof is composed of a horny material that is produced continuously and must be worn off or trimmed off. The hoof wall does not contain blood vessels or nerves.

In the front feet, the wall is thickest at the toe; in the hind feet the hoof wall is of a more uniform thickness. The wall, bars and frog are the weight-bearing structures of the foot. Normally the sole does not contact the ground.


 



 


Figure 2a - Internal structure of the horse foot.


Internal structure of the horse foot



These cartilages are flexible, but as the horse ages, they are usually ossified and replaced by bone. Between the second and third phalanges and above the deep flexor muscle tendon is a small bone called the navicular bone (Figure 2b).



Internal structure of the horse foot


 Inside the hoof, lateral cartilages extend back and up from the inner and outer sides of the third phalanx. (Figure 2a).


                          Figure 2b - Internal structure of the horse foot.


The navicular bone and its associated bursa — a fluid-filled sac that reduces friction between the tendon and the bone — are involved in navicular disease, which is a common cause of lameness.


 


Figure 2c - External structure of the horse foot.



External structure of the horse foot Flexible structures in the horse's hoof expand and contract with each step as weight is transferred from one foot to another.

The digital cushion is a mass of flexible material that contributes to the formation of the heels (Figure 3). This structure is one of the primary shock absorbers of the foot.

As weight is placed on the hoof, pressure is transmitted through the phalanges to the wall and onto the digital cushion and frog. The frog, a highly elastic wedge-shaped mass, normally makes contact with the ground first. The frog presses up on the digital cushion, which flattens and is forced outward against the lateral cartilages.


Figure 3 - The frog also is flattened and tends to push the bars of the wall apart.


Flexible structure in the horse's hoofWhen the foot is lifted, the frog and other flexible structures of the foot return to their original position.

When the foot is placed on the ground, blood is forced from the foot to the leg by the increase in pressure and by the change in shape of the digital cushion and the frog.

The pressure and the change in shape compress the veins in the foot. When the foot is lifted, the compression is relieved and blood flows into the veins again. In this way, the movement of these structures in the hoof acts as a pump. Exercise increases the blood circulation in the foot and favors good hoof growth. Lack of exercise, dryness of the horny wall, and poor nutrition inhibit hoof growth.

Normally, the hoof wall grows at the rate of about three-eighths inch per month. New layers of hoof wall are produced continuously from just below an area called the coronet at the junction of the skin and the hoof wall (Figure 2c).

The hoof wall is covered with material that prevents evaporation of moisture. When this material is deficient, the hoof wall becomes dry and excessive flaking and cracking may occur. A good hoof paint aids in preventing excessive drying.

This publication was originally written jointly by Robert C. McClure, Gerald R. Kirk and Phillip D. Garrett. Kirk and Garrett are former faculty members in the Department of Veterinary Anatomy, College of Veterinary Medicine. Illlustrations are by Phillip D. Garrett.

 


 


 



 

Fallen crest

A  large crest or fallen crest refers to a horse that has an overly large crest to it's neck that may fall to one side in extreme cases.

Fallen crests are relatively uncommon, although any horse can develop an excessively large crest. It is usually seen in stallions, ponies, Morgans, and draft breeds.

It is usually from fat deposits above the nuchal ligament. An excessively large crest not only looks bad, but it puts more weight on the forehand. A horse with an excessive crest due to obesity needs a proper conditioning program.

White Brindle Left Side Only

Brindle is a rare color for horses, although it occurs frequently in cattle and dogs. These pictures of a white brindle horse are of a 2002 Dutch Warmblood mare by Celano, imported from the Netherlands in May 2008. Her pattern is strictly on her left side, even throughout her mane and tail. She seems to have a seam along her backbone the brindle markings don't cross. However, she has a few funny little circles on the right side on her head and neck.
















White Brindle Horse
White brindle horse picture Right side of horse
White brindle left side of tail White brindling only on left side
White brindle color pattern Note white pattern on left side only
white brindling on horse

Akhal-Teke Genetic Diseases

Akhal Tele Hairless Colt

There are several genetic diseases of concern to Akhal-Teke breeders. The genetic diversity of the breed is relatively low with an AVK of 30-50%, which raises concerns for dealing with an increase in carriers of these conditions, and even some risk of inbreeding depression. To date, there are no DNA tests for these conditions.



Hairless Akhal-Tele colt caused by a genetic disorder


Naked Foal Syndrome or Hairless Foal Syndrome is most likely an autosomal, lethal recessive gene, though the exact inheritance pattern has not yet been verified. It appears to be similar in clinical signs, though not identical to junctional epidermolysis bullosa (JEB) found in the Belgian horse and another condition of a similar nature identified in the American Saddlebred.


The defect causes foals to be born without any hair coat, mane or tail. In some cases, the front teeth are in at birth or molars grow abnormally from normal jaws. Other symptoms include persistent diarrhea, frequent digestive disorders and laminitis-like, treatment-resistant rotation of the coffin bones in the hooves.


Due the lack of normal skin protection, secondary symptoms include scaly, dry and inflamed skin, as well as severe cases of sunburn in summer and frequent pulmonary infections during winter. NFS is always fatal, most foals die within weeks of birth, although some horses have survived up to the age of two years.


Early demise is usually caused by digestive problems, whereas older horses need to be humanely euthanized because of severe laminitis-induced pain. Cases were recorded within the Akhal-Teke breed as early as 1938. In spite of the breed's limited population, naked foals have been born in every country in which the breed is represented, including the USA.


Some 35 carriers have been ascertained, including 943 Arslan, 736 Keymir, 2001 Mariula or 1054 Gilkuyruk, but the estimated number of unknown cases is very likely much higher, as several Russian and Turkmenian breeders have acknowledged that many NFS foals are often just reported as stillborn or aborted.


Hereditary cryptorchidism is very common within the Akhal-Teke breed and many cases exist where afflicted stallions can be traced through multiple generations. The influential foundation sire, 2a Boinou, was a cryptorchid according to experts of the breed. Other verified cryptorchids include 779 Peren, 1248 Orlan, 971 Khalif, and Garayusup. 1069 Kortik produced three cryptorchid sons. Unlike most European and many North American breed organisations, neither Russia nor Turkmenistan bar cryptorchids from breeding. Cryptorchidism is said to be related to health and character problems, such as testicular cancer and malignant behaviour. Affected horses cause significantly higher costs when castrated.


Wobbler syndrome, seen in a number of breeds, including the Thoroughbred, is thought to be on the increase in the Akhal-Teke. Of particular concern is the form known as cervical vertebral malformation (CVM), which may also be linked to Osteochondritis dissecans (OCD) to a certain extent. There is a genetic component to Wobbler's, but factors such as breeding Akhal-Teke horses for certain conformation in the neck and management of young stock for forced growth and greater size may also play a role.


The Akhal-Teke is one of several breeds that is prone to degenerative suspensory ligament desmitis (DSLD) Some animals also have a condition known as "Kissing Spine."

What is the ‘horsepower’ unit of measurement based on?

Horsepower (HP) is the name of several units of measurement of power. The most common definitions equal between 735.5 to 746 watts. The horsepower is not recognized in the International System of Units (SI).


The horsepower was originally defined to compare the output of steam engines with the power of draft horses. The unit was widely adopted to measure the output of piston engines, turbines, electric motors, and other machinery. The definition of the unit varied between geographical regions. Most countries now use the SI unit watt for measurement of power.


The definition of the horsepower also has varied between different applications:



  • The mechanical horsepower of 550 foot-pounds per second is approximately equivalent to 745.7 watts.

  • The metric horsepower of 75 kgf-m per second is approximately equivalent to 735.499 watts.

  • The boiler horsepower is used for rating steam boilers and is equivalent to 34.5 pounds of water evaporated per hour at 212 degrees Fahrenheit, or 9,809.5 watts.

  • One horsepower for rating electric motors is equal to 746 watts.

  • The Pferdestärke (German translation of horsepower) is a name for a group of similar power measurements used in Germany around the end of the 19th century, all of about one metric horsepower in size.

  • The Royal Automobile Club (RAC) horsepower or British tax horsepower is an estimate based on several engine dimensions.

The development of the steam engine provided a reason to compare the output of horses with that of the engines that could replace them. In 1702, Thomas Savery wrote in The Miner's Friend: "So that an engine which will raise as much water as two horses, working together at one time in such a work, can do, and for which there must be constantly kept ten or twelve horses for doing the same. Then I say, such an engine may be made large enough to do the work required in employing eight, ten, fifteen, or twenty horses to be constantly maintained and kept for doing such a work…"


The idea was later used by James Watt to help market his improved steam engine. He had previously agreed to take royalties of one third of the savings in coal from the older Newcomen steam engines. This royalty scheme did not work with customers who did not have existing steam engines but used horses instead. Watt determined that a horse could turn a mill wheel 144 times in an hour (or 2.4 times a minute). The wheel was 12 feet in radius, therefore the horse travelled 2.4 × 2π × 12 feet in one minute. Watt judged that the horse could pull with a force of 180 pounds. So:


formula for horsepower


This was rounded to an even 33,000 ft·lbf/min.


Others recount that Watt determined that a pony could lift an average 220 lbf (0.98 kN) 100 ft (30 m) per minute over a four-hour working shift. Watt then judged a horse was 50% more powerful than a pony and thus arrived at the 33,000 ft·lbf/min figure.


Engineering in History recounts that John Smeaton initially estimated that a horse could produce 22,916 foot-pounds per minute. John Desaguliers increased that to 27,500 foot-pounds per minute. "Watt found by experiment in 1782 that a 'brewery horse' was able to produce 32,400 foot-pounds per minute." James Watt and Matthew Boulton standardized that figure at 33,000 the next year.


Most observers familiar with horses and their capabilities estimate that Watt was either a bit optimistic or intended to underpromise and overdeliver; few horses can maintain that effort for long. Regardless, comparison with a horse proved to be an enduring marketing tool.


A healthy human can produce about 1.2 hp briefly (see orders of magnitude) and sustain about 0.1 hp indefinitely; trained athletes can manage up to about 2.5 hp briefly and 0.3 hp for a period of several hours.


Horsepower from a horse


R. D. Stevenson and R. J. Wassersug published an article in Nature 364, 195-195 (15 July 1993) calculating the upper limit to an animal's power output. The peak power over a few seconds has been measured to be as high as 14.9 hp. However, for longer periods, an average horse produces less than one horsepower.

Abtenauer horse breed

The Abtenauer is a rare draft horse breed. It is the smallest variant of the Noriker horse, but is very strong despite its small size. Their population numbers are very low and the breed is critically endangered.

Bull Neck

Bull Neck

The horse with a bull neck has a short, thick, and beefy neck with a short upper curve. The attachment to its body is beneath the half-way point down the length of shoulder. This trait is fairly common, especially in draft breeds, Quarter Horses, and Morgans.

With a bull necked horse, it is generally more difficult to maintain balance if the rider is large and heavy or out of balance, which causes the horse to fall onto its forehand. Without a rider, the horse is usually fine.

A bull neck is desirable for draft or carriage horses, so as to provide comfort for the neck collar. The muscles of the neck also generate pulling power.The horse with a bull neck  is best for non-speed sports.

Overshot jaw (parrot mouth) or undershot jaw (“monkey jaw” or “sow mouth”)

Horse with overbite

An overshot jaw is when the upper jaw extends further out than the lower jaw, with the horse having an overbite (also called a parrot mouth). When the lower jaw extends farther out than the upper jaw, we call this and undershot jaw,with the horse having an underbite (also referred to as a monkey jaw or sow mouth).

Both defects can affect the chewing of the horse and the horse's ability to clip grass. Both defects are fairly rare in the horse species.

Destrier Horse

The destrier is the best-known war horse of the medieval era. It carried knights in battles, tournaments, and jousts. It was described by contemporary sources as the Great Horse, due to its size and reputation.

Bronco, or bronc

Bronco, or bronc, is a term used in the United States, northern Mexico and Canada to refer to an untrained horse or one that habitually bucks. It may refer to a feral horse that has lived in the wild its entire life, but is also used to refer to domestic horses not yet fully trained to saddle, and hence prone to unpredictable behavior, particularly bucking. The term also refers to bucking horses used in rodeo "rough stock" events, such as bareback bronc riding and saddle bronc riding.

In modern usage, the word is seldom used any longer to refer to a "wild," or more accurately, a feral horse, because today, the modern rodeo bucking horse is a domestic animal. Some are specifically bred for bucking ability and raised for the rodeo, while others are spoiled riding horses who have learned to quickly and effectively throw off riders. Informally, the term is often applied in a joking manner to describe any horse that acts up and bucks with or without a rider. The Wild Horse Protection Act prevents the capture of mustangs from the wild for commercial use, and though the law has been weakened in recent years, "wild" mustangs and other completely untamed horses are still no longer used on the rodeo circuit, as bigger, more powerful animals that are sufficiently domesticated to be handled from the ground for veterinary care, travel, and stabling in small pens are more desirable as rodeo stock.

The term comes from the Spanish language word bronco, meaning "rough", which in Mexican usage also describes a horse. It was then borrowed and adapted in US cowboy lingo. It has also been spelled "broncho," though this form is virtually unknown in the western United States, where the word is most common. Many other instances of cowboy jargon were similarly borrowed from Mexican cowboys, including words such lariat, chaps, and buckaroo, which are in turn corruptions of the Spanish la riata, chaparajos, and vaquero.

In the early American west, most cattle ranches simply allowed young horses to grow up in a feral state on the open range, capturing them at maturity to be broken-in or "broke" to make them tame enough to ride. Sometimes mustangs were rounded up as well, as the two populations often mixed.