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

Horse Terminology

Horse Terminology

Tölt Gait

The Tölt (also, less correctly, Tolt) is a gait that is often described as being unique to the Icelandic Horse. In its pure form, the footfalls are the same as in rack, but the gait in the Icelandic horse has a different style with more freedom and liquidity of movement. The most prized horses have a very long stride and considerable lift with their forelegs. Icelandic Riders will demonstrate the smoothness of a tölt by going at the speed of a gallop without spilling a drink they hold. However, some horses have a tölt that is considered imperfect, and may be described as a "trotty tölt" or a "pacey tölt".The Tölt differs from the rack as the horse is not supposed to hollow its back.


The majority of Icelandic horses can also perform a type of pace called flugskeið or a "flying pace," and are thus called "five-gaited". (Walk, trot, canter, tölt, pace.) Good pacers are held in high regard in this breed, but for a pacer to stand out the horse has to be able to perform the pace at a high speed.Slow pacing in Icelandic horses is considered a major flaw. A horse that goes at a slow pace, or "piggy-pace," is referred to as lullari.


The Faroese Horse and the Nordlandshest/Lyngshest of Norway share common ancestry with the Icelandic horse and some individuals of these breeds have the capacity to tölt, although it is not as commonly used.

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


 

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.

Zorse, Hebra, Zony, and Zonkey Pictures and Names (Half zebra and half horse or donkey)

Zorse foal



Hybrid animals are often referred to by a portmanteau formed by combining the names of the two parent species: traditionally the father's species forms the first part of the name, hence:


male Zebra + female horse -> Zorse


male horse + female zebra -> Hebra

So, a zorse is a cross between a zebra stallion and a horse mare. The zorse takes the color or dominant color gene of the mare and the zebra sire gives it stripes.  Zebra stallions usually must be raised in a special environment to induce them to breed horse mares.


 ZorseA hebra is a cross between a zebra mare and a horse stallion – the rarest of equine inter-species breedings. Horse stallions as a general rule do not like to breed zebra mares. 


A zony is a cross between a zebra stallion and a Shetland Pony mare.


A Zonkey  (also known as zebrass, zebronkey, zeedonk, zedonk, zebadonk, zenkey, donbra, donbri, donkra, zebrinny, zebrula, or debra) is a cross between a zebra stallion and a donkey jennet (also called a jenny).


"Zonkey" is not the technically correct name for such a cross. The most commonly accepted terms are zebrinny, zebrula, and zedonk.


Buckskin ZorseA zebrinny is the offspring of a male zebra and a female ass, called a jenny; a zebrula is the offspring of a male zebra and a female horse; a zedonk is the offspring of any zebra and any donkey.


The zonkey takes the color or dominant color gene of the jennet (also known as a jenny) and the zebra sire gives it stripes.


The zonkey is generally more easily bred for than the zorse as the donkey and zebra both communicate behaviorally using very similar language, but horse language is somewhat different than the zebra's. 


 A group of horses is a herd and a group of zebras is a zeal.


What is a Zorse?


A zorse or zebrula is a zebroid, specifically the offspring of a zebra stallion and a horse mare.  


Like most other hybrids, the zorse is infertile.


Zony PictureAn interspecific hybrid is created when a male and female from two closely-related species (usually from the same genus) mate and produce offspring. This offspring shares characteristics with both its parents. Normally hybrids are sterile: this prevents genetic characteristics from passing between the two gene pools and thus explains why they are two distinct species. This sterility is sometimes due to a difference in the number of chromosomes: for example, donkeys have 62 chromosomes, horses have 64, mules have 63, and the zebra has between 32 and 46 (depending on species). Rarely, however, a fertile hybrid will appear.






White zorseA hybrid has a number of chromosomes somewhere in between. The chromosome difference makes female hybrids poorly fertile and male hybrids sterile due to a phenomenon called Haldane's Rule. The difference in chromosome number is most likely due to horses having 2 longer chromosomes that contain similar gene content to 4 zebra chromosomes.


The rarity of zebra hinnies and hebras indicates that the smaller number of chromosomes must generally be on the male side if a viable hybrid is to be produced. Before this comes into account, a successful mating needs to be accomplished in the first place.


Trained ZorseCourtship in horses involves the mare kicking at the stallion's head for some time before allowing him to mount, and as this behavior is stronger in wild equids than in domestic horses, it is difficult enough to get a horse stallion to mate and not be put off by the rough behavior of the non-horse mare. Thus the zorse is much more common than the hebra. In fact, there are only a few known hebra hybrids living.


Many hybrids result from animal husbandry by humans, however interspecific mating is not unknown in the wild. For example, DNA tests have confirmed that a bear shot to death by a hunter in Canada's Northwest Territory was a grizzly/polar bear hybrid. This confirmed scientists' hypothesis that a hybrid zone where such births naturally occur might exist where the two species' habitats overlap.


Hebra PictureThe zorse is a strong animal with traces from both its parents. James Cossar Ewart crossed a zebra stallion with horse and pony mares in order to investigate the theory of telegony, or paternal impression. Cossar Ewart used Arabian mares. Similar experiments were carried out by the US Government and reported in "Genetics in Relation to Agriculture" by E.B. Babcock and R.E. Clausen, and in "The Science of Life" by H.G. Wells, J. Huxley and G.P. Wells (c.1929).


Zorses are also bred in Africa and used for trekking on Mount Kenya.


Coloration of the Zorse


It is common for people to think a hebra mating produces the solid white patches, such on the animal pictured above, because this animal is one of the few hebras in existance and this picture is widely circulated. Since most people haven't seen another hebra picture, they think it must be the horse stallion - zebra mare mating that produces this color pattern. However, this is not the case.


Zedonk (Zonkey) pictureBoth Zorses and hebras combine the zebra striping overlaid on colored areas of the hybrid's coat. Zorses are most often bred using solid color horses. If the horse parent is piebald (black and white) or skewbald (some other color and white) (these are known in the USA as paint/pinto) the zorse may inherit the dominant de-pigmentation genes for white patches.


It is understood that Tobiano (the most common white modifier found in the horse) directly interacts with the Zorse coat to give the white markings. Only the non-depigmented areas will have Zebra striping, resulting in a zorse with white patches and striped patches.


Zorse ande RiderIf the mare has a pattern, such as pinto spotting or Appy spots, the zorse often will also.


This effect is seen in the zebroid Eclyse (a hebra rather than a zorse - pictured above) born in Stukenbrock, Germany in 2007 to a zebra mare called Eclipse and a stallion called Ulysses.


Breeders avoid using gray mares because the zorse can inherit the graying gene and lose all his stripes in a few years! Even if they lose their stripes, you can still see the stripes on the skin.


Temperament of the Zorse


Young ZonkeyZony - cross between Zebra and Shetland PonyThe temperament of a zorse, hebra, zony, or zonkey is more like that of the donkey, than the horse. This is not an animal for a novice to handle. Zebras are quite strong for their size and very aggressive in the wild. They possess a highly developed flight or fight survival response to anythng they perceive as dangerous or frightening. The first defense in this psychology is to run away from danger. But, if they can't escape, the next defense is to fight for their lives, and they will. In the wild, zebras win at least as often as the predators who hunt them. This instinct is hundreds of times stronger in a wild animal than a domestic breed.


For example, our common dog breeds are descended from wolves and scientists estimate it took as much as 100 generations for some breeds to become the docile, trusting beasts we keep in our homes today. It takes a minimum of three generations for these wild instincts to begin to dim, and often much longer, before we consider their intensity to be fully domestic. At this time, most zorse and zeadonk crosses are F1s, meaning one parent is a full blood zebra, although there are some on the market that are as much as F17s. Of course an F17 would be a lot more predictible than an F1. You get the idea.These animals are definitely more flighty and stubborn than horses and they can be quite aggressive, so you should have a great deal of horse experience before deciding to get one.


It helps a lot if the mare has a good disposition. Generally, the offspring inherits the striping pattern and some of the conformation of the zebra sire with the size, colouration, and temperament of the domestic mare.You will still have to work harder than with a horse to overcome the natural wild instincts of the zebra, but it helps if the mare doesn't have a nasty dispostion, too.


Males should be gelded as early as a few months old to prevent dangerous studdy behaviour.


Zorse with zebra father

Why the Zorse was originally bred


The crosses of zebras with horses, donkeys and ponies were originally done in England and Africa to try to produce a domestic horselike animal that was resistant to diseases spread by the tse tse fly in Africa. Zebras have natural resistance, where domestic donkeys and horses do not.


 


The experimental crosses were actually becoming popular until early in the 20th century when the auto displaced the horse and mule. At that point cross-breeding was largely abandoned. A revival of interest came in the early 1990s, with just about every breed of domestic horse imaginable is being tried.


Mares of quality, especially Quarter horses and American Paint horses, produce some very beautiful zorses that have a good working attitude.


Longevity of Zorses


Zorses tend to be very hardy and live into their 30s with good care. Their temperaments are generally similar to those of their mothers, but like the zebra they do have a strong flight response. Because of this it's best for a first time hybrid owner to get a zedonk instead. When a zedonk startles he freezes up like a donkey rather than bolting blindly like a horse or zebra.


A gorgeous chestnut zorse


Closeup of Zorse Stripes