Learn the Terms, Differences, and Types
Quick Reference of Terms
Jack + mare = mule
Stallion + jennet = hinny
Jack + mule = jule, or donkule
Stallion + mule = hule
Male mule = horse mule, or john mule
Female mule = mare mule, or molly
A hinny resembles a horse more than an ass. It looks more like a horse with long ears.
The mule is a cross between a male donkey [jack] and a female horse [mare].
The hinny is also called a mule, but is crossed between a male horse [stallion] and a female donkey [jenny, or jennet].
The Difference between Mules and Hinnies
The feet [hooves] of a hinny are more like a donkey, narrow and more upright, and the mule’s hooves are more horse-like. However, a bit more angle than the donkey hoof but not as round and angled as the horse. Both mules and hinnies should be trimmed more upright and the heels left longer than a horse.
Both mule and hinnies have more endurance than the horse, more resistance to disease, and have much stronger hooves. They require less feed, and are less likely to be startled or spooked. The horse has a flight reflex when startled and the donkey is more likely to freeze and evaluate the situation.
Mules and hinnies are often mistaken as stubborn; however their self-preservation is what in fact keeps them safe. Mules and donkeys may also have flight reflexes; it just depends on the specific animal and the situation.
From the donkey a mule inherits intelligence, endurance, quite extraordinary strength, and patience. His speed and beauty is from the horse.
Equine: Mammals, members of the family Equus. These are single-toed (hooved) grazing animals. Equines are horses and ponies, donkeys, wild asses, zebras, and the equine hybrids resulting from the crossing of two different species (such as donkey x horse = mule, zebra x donkey -zebrass)
Sire : the male parent of an equine.
Dam: (pronounced as it looks) the female parent of an equine.
Stud: The breeding male of a species, or, the breeding farm housing a stud (stallion or jack).
Get: The offspring of a Jack or Stallion. The male is said to “get” the offspring on the female, thus the collective term get for his young. The class for this is
Get of Sire. By means sired by. The young by the same stud are shown together as a group. The term “out of” refers to the female and not the male.
Produce: The offspring of a Jennet or Mare. The females produce the young.
The term “out of” is literal in the sense that the foal was born out of that female. The Produce of Dam are shown in special classes the same as in the Get of Sire. (Blackjack x My Jenny is read as “By Blackjack out of My Jenny”)
Hand: The unit of measurement for the equine. One hand equals four inches. Equines are measures from the ground to the highest points of the withers. A measuring stick with a cross piece and level is the preferred method. Height listed in hands are given as hands+inches. !3.3 means 13 hands, 3 inches.14.2 would be fourteen hands, 2 inches. 14.3 3/4 is fourteen hand, three-and-three quarters inches. There is no 13.4 or 14.4 – when you reach 4″, you just add another hand.
More About Mules
The Mule is a cross between a donkey stallion (called a jack) and a horse mare. Hinnies are just the opposite – a stallion horse crossed to a donkey jennet. For all purposes, hinnies and mules are classified and shown together under the general term Mule. A mule or hinny may be a male (horse mule or horse hinny) or a female (mare mule or mare hinny). Sometimes horse mules (the males) are called Johns, and the mares are called Mollies. Both male and female mules have all the correct “parts” but they are sterile and cannot reproduce. A VERY few (about 1 in 1 million) mare mules have had foals, but these are VERY, very rare. No male mule has ever sired a foal. SO if you cross a mule to a mule – you get nothing! Mules and hinnies must be bred by crossing a donkey and horse every time. (Male mules should also be castrated, since they are sterile. They can become dangerous with too many hormones, so should always be castrated. You can’t show an intact male mule, anyway, and it is useless to keep them a stallion).
Mules ears are usually somewhat smaller than a donkeys, longer but the same shape as the horse parents. The mule’s conformation will be a combination of traits from both parents. The head, hip and legs usually take after the jack. Mules do not have pronounced arches to the neck, even from breeds such as Arabians or Warmbloods. A slight arch or straight neck is preferable to a ewe, or upward curved neck.
The mule will have “combination hair”, usually a thin forelock, coarse mane hair, and a tail more like the horse parent. Both mules and donkeys are shown with a variety of hairstyles from clipped to shaved (roached). Mules may wear their tails “belled” as decoration, left long and full, or clipped at the top to emphasize the shape of the hip.
Mules try their best to imitate the donkey’s bray, but most have a unique sound that is a combination of the horse’s whinny and the grunting of the wind-down of a bray. Most will start out - Whinee…..and end in “-aw ah aw”. Every mule or hinny will have a unique bray.
Mules usually have brown or tan-colored points, where in the donkey the Light Points are a shade of off-white. Some donkeys and mules do not exhibit any light points at all – this is not usual (due to a recessive gene) , but is a good identification marker for registration purposes. Old-timers used to call a dark muzzled mule “blue nosed”. Mules can be any of the colors that either horses or donkeys come in, along with some unique variations of their own.
The only colors mules do NOT come in is true horse pinto (due to the genetic factoring of these colors, there are some mules who are close to, but not quite, tobiano patterned, and none recorded in overo). Mules from Appaloosa mares often have extremely loud patterns, with spots enlarging or “skewing” in variants of the horse appaloosa. Breeders wishing for a mule with four white feet should try a tobiano mare. The mule will probably have four socks and/or stockings, with the most usual combination being four white feet and a splash of white on the tail. The genes of the mule seem programmed for the unusual, and very strange, loud spotted pinto and appaloosa variants are common. In fact, the best way to produce a spotted mule is to cross a spotted jack to a solid colored mare. The resulting mule may have pinto-like patches in a variation of the donkey-spot pattern. Appaloosa mares crossed to spotted jacks have often produced mule foals that appear to be roan-patched pinto, with dark leopard appaloosa spots over the dark areas.
Mules come in every size and shape imaginable. Miniature mules (even to under 36″) can be seen all the way up to 17 hand Percheron draft (by Mammoth Jacks) Mules. The Poitou donkey was used exclusively for breeding huge draft mules from a breed of draft horse called the Mullasier – the Mule producer. The build of the mule is a combination of both parents. The head resembles both, the eyes being more almond-shaped (inherited from the D-shaped eye socket of the donkey). Male mules may have more prominent brow ridges like those of most donkey jacks. The neck is straight and has little arch, even in mules from Arab or Warmblood mares. The overall body shape will be dependent on the conformation of both parents.
Due to hybrid vigor, the mule has the possibility of growing taller than either parent.
The rarer Hinnies are often said to be more horselike than the mule, but more often it is impossible to tell them apart. Hinnies may tend to be slightly smaller, simply because of the fact that most donkeys are smaller than horses. Mules can be used in exactly the same sports as horses – under saddle, in harness, for cutting, roping or dressage. In actuality, they have more stamina and can carry more weight than a horse of equal size. This is due to the hybrid vigor. There is one particular aspect where the mule actually outshines the horse, and that is high-jumping. Mules have a particular sport all their own called the Coon Hunter’s Jump. It stems from the raccoon hunter moving his saddle and pack mules through the woods. Wooden or stone fences could be taken down, but wire ones could not. The hunter would flag the fence with his coat or a blanket, and jump his string of pack mules over one by one. In the showring, mules jump a single rail standard to increasing heights. The last clean jump is the winner. Mules only 50 inches tall at the withers have been known to clear jumps of up to 72 inches. These jumps are not from a galloping approach, like Puissance, but from a standing start inside a marked area. Truly a remarkable feat.
Mules are not really stubborn. They can seem lazy because they will not put themselves in danger. A horse can be worked until it drops, but not so with a mule. The “stubborn” streak is just the mule’s way of telling humans that things are not right. Mules are very intelligent and it is not a good idea to abuse a mule. They will do their best for their owner, with the utmost patience.
Modern American Asses = All Types Classified by Height
All of the types listed are registered by ADMS. (There are few true BREEDS of donkeys, especially in the US. Donkeys in the US are classified by type or height, while foreign breeds may exist – A breed must be of the same type and usually has a studbook backing it. )
Miniature Mediterranean Donkey: Originally imported from the Italian islands of Sicily and Sardinia, and other Mediterranean areas, these donkeys must be under 36″at the withers at maturity (after age 3) to be registered with ADMS as a Miniature. (At the current time, donkeys up to 38″; may be listed as O for Oversize ONLY if they have a traceable pedigree of Registered Miniature parents. Both Parents must be registered Miniatures). These animals are registered by all legitimate American Donkey or Canadian registries, including the American Council of Spotted Asses. The are often referred to as Sicilian Donkeys, but this is not correct usage, nor is Sicilian the name of the typical coloration of these donkeys. The ADMS now registers these animals in the Miniature Donkey Registry, although ADMS also has some older animals listed in the American Donkey Registry as well.
Standard Donkey: This covers the size range of most donkeys in the world. The size range is from 36.01″ to 48″; at the withers. This size donkey is often called a “burro”. (Most but not all of the background is Spanish stock)
Small Standard Donkey: A subdivision of the Standard grouping. Small standard stand above 36″ and up through 40″, often with a miniature background. This includes donkeys up to 38″ if they have no registered miniature parents or traceable miniature pedigree.
Large Standard Donkey: Donkeys from 48.01″ up to 54″ for females and up to 56″ for males. These are good riding donkeys or can be used in breeding saddle mules. Many may have Mammoth breeding in their background.
Mammoth – Mammoth Jackstock, Mammoth Ass – This is one of the largest breeds of donkey in the world. Once referred to as American Standard Jack Stock. Males must stand 56″ and up, females must be 54″ and up. These animals have their own registry, the American Mammoth Jackstock Registry (formerly Standard Jack and Jennet Registry) and are also registered in the ADMS American Donkey Registry.
American Spotted Ass. While all asses can come in the spotted pattern (“pinto”), the term American Spotted Ass is a trademark for those donkeys (asses) registered with the American Council of Spotted Asses (ACOSA), which is trying to establish foundation stock for spotted asses. For those interested in genetics: At this time, it is not known if the spotting gene can be homozygous (SS) as in the horse tobiano, as spotted jacks and jennets are still seen to throw non-spotted (solid) foals, meaning they are still heterozygous (Ss) for spots.
Ass: The correct term for the animal commonly known as the donkey, burro, or jackstock. The term comes from the original Latin term for the animal which was Asinus. The scientific term for these animals is Equus asinus. The term fell into disrepute through confusion with the indelicate term “Arse” meaning the human backside. You are never at fault when you refer to one of these animals as an ass, and the term is not improper unless you misuse it so yourself. The difference between asses and horses is a species difference. You might compare it to the differences between zebras and horses, different species but closely related and able to interbreed to a degree.
Jack: The term used for the male of the ass species. Thus, the often used term Jackass – which is correct if redundant. Jacks are called stallions in the UK, but stallion is reserved for horses and zebra males in the US.
Jennet: Pronounced JEN-et, the correct term for the female of the species. The more commonly used term is Jenny, which is considered correct in non-technical use. The term mare is used for horse and zebra females in the US. (But a jennet is a mare in the UK)
Burro: A word taken directly from Spain. It means the common, everyday working donkey found in Spain and Mexico. It came into usage in the Western United States. As a general rule, the term burro is heard West of the Mississippi and the term Donkey, east of the Mississippi. Burro is not appropriate for use in referring to Miniature Donkeys or Jackstock.
Wild Burro: These are the feral (descended from domestic stock that has gone wild over generations) asses which run wild in the Western part of the United States. The American Donkey and Mule Society and Bureau of Land Management (who are in charge of the Wild Burro population) prefer to keep the term Burro for these animals. When registering they are listed as
“Standard Donkey” and the origin and breeding is given as Wild Burro.
Donkey: Taken from England, the derivation is uncertain, but most authorities think that the name comes from dun (the usual color) and the suffix “ky” meaning small. Thus “a little dun animal”. In earlier England the word Ass was taken from the Roman word for the animal. “Donkey” is a relatively recent variation of the species name.
Jack Stock: (Jackstock) The term for plural of the American Mammoth Jack and Jennet. These animals are properly termed Asses and not donkeys, and never called burros. They are one of the largest of the types of the ass species.
Gelding Donkey: The proper term for a gelded (castrated, or “altered” male ass. An informal term is John (a modified form of Jack).
Spanish Jack or Spanish Donkey: ADMS does not accept this terminology unless the animal has written documented proof of importation of itself or its immediate ancestors from Spain. This holds for animals which people call by the breed names of foreign breeds such as Catalonian, Maltese, or Andalusian. These breeds as pure strains are rare even in Spain, and are non-existent in the US. The term Spanish Donkey is found in common usage meaning a large standard donkey The ancestry of most of the donkeys in the United States is predominantly a blend of all of the Spanish breeds. In any case, the term is inexact and is not good usage.
Mule Jack: Not a mule, but a jackass used to breed mares to obtain mules.
Jennet Jack: a jackass used to breed to jennets (the female of the species) in order to produce more donkeys. A good breeder uses only the finest of jacks for this purpose.
British Terms: You may read English books on donkeys. For some reason, the terms jack and jennet have been abandoned and turned to stallion and mare instead. Also, a hinny is commonly called a jennet in England.
The Cross: Refers to a line of darker hairs starting at the top of the head and running to the end of the tail. (Dorsal stripe) This is crossed at the withers with another darker line of hair (the shoulder stripe) forming a cross. The shoulder stripe may be long, very short, thin, wide, fading or dashed, but nearly all donkeys have some form of this marking. The exceptions are the Mammoth asses which have been bred away from this marking, and true black animals where the cross is not visible. Even spotted animals or white-appearing donkeys may have partial or faint crosses. This trait is very dominant. The presence of this marking on donkeys has led to many lovely legends in the Christian religion. The term Jerusalem donkey is often incorrectly applied to donkeys with the normal cross marking. It is a nickname, and not a true breed or type.
Markings: In addition to the cross, many donkeys have dark markings on the ears, as “garters” (zebra marks) around the legs, or as “zippers” down the inside of the forelegs. Small black spots on the sides of the throat, called collar buttons, may also be seen, as well as a dark line (ventral stripe) down the belly.
White Points: When registering donkeys, white points are so universally normal that only the absence of them is to be noted. It is normal for a donkey to have short, fine, light colored hair on the muzzle (although the lips themselves will have darker hair), ringing the eyes, on the belly and inside of the legs. A donkey that does not have these points is seen as unusual but are not too uncommon. The gene for No Light Points (*NLP) appears to be recessive. A few donkeys will have only a small patch of lighter (tan, not the usual soft white) hair only a the side of the muzzle, with dark around the eyes and a tan belly. This is noted in registration papers as an Intermediate Black
Muzzle: Just having dark lips, with the fine muzzle hair being light, is not a black muzzle.
Common Sizes of Mules or Donkeys
Miniature = 36″ or less at the withers
Small Standard = 36.01″ up to 40″
Standard = 40.01″ up to 48″
Large Standard = jennets are 48.01″ up to 54″, jacks are 48.01″ up to 56″
Mammoth = jennets are 54.01″ and over, jacks are 56.01″ and over