The Mule

A mule is a hybrid of a horse and an ass or donkey. He is the progeny of a male donkey -- a jack , and a female horse -- a mare. A hinny or jennet is the progeny of a male horse and a female donkey. The mule is considered to be the most successful hybrid ever developed. It has been the backbone of the equine trade, and has been more the working animal doing the work of farm tractors and trucks today, while the horse is likened more to the passenger or sports cars. The proper term for a male mule is "horse mule," but they are sometimes called a John mule. A female is properly called a "mare mule," though she may often be called a Molly mule. Hinnies follow the same pattern with "horse hinny" and "are hinny."

Hybrid vigor, or heterosis, is a term to identify extra qualities likely to be inherited by the offspring produced from two different species of equids. Mules are likely to exhibit greater strength and endurance, be larger in body size and survive better on poorer food than either of its parents. Sterility is another inherited hybrid trait, caused by the kinds of chromosomes being unequally matched -- the horse has 64 sets, while the donkey has 62. The mule's resulting chromosome count is 63, and that makes it unable to reproduce itself. They still possess both internal and external reproductive organs, therefore it is necessary to geld a male mule to make him more compliant. A female may come into heat and sometimes may accept a male. Some females even nurture the foals of other mares, even though they never had a foal.

There is one documented case of a fertile mule, Old Beck, where she produced two offspring. One was described as a typical female "mule" by a donkey, and the other as a male "horse" sired by a stallion. The son of Old Beck went on to sire a number of foals from mares, none showing any reversion to the donkey ancestry. There have been a total of 14 documented cases in American history of mules producing foals.

Family traits as the head and tail are generally passed on from the sire, and size is usually limited by the dam. The mule generally resembles a donkey with a horse body, while the hinny usually has the smaller donkey body with a head and tail like its sire. The mule has a heavy head with long ears, a donkey-like mane, and a horse-like tail that is wispy and sparse. He has fine-boned legs with small hooves and almost flat withers, and is said to be 25% more powerful than any other equine relative to its size. Conformation is ideal for carrying a pack saddles as the back is long and virtually straight from withers to croup. A mule has a narrower body than a horse of the same height and weight. Traits inherited from the mare tend to include talents as "cow sense," jumping ability and gaits, while the physical characteristics come from the Jack.

Because the mule is reared by a mare, it generally detests the asinine race and adores the whole horse race. A mule team may pull harder and faster if led by a mare, and many American mule-train were led by a mare with a bell tied around her neck.

The head of a hinny is lighter and more horse-like, Ears are much shorter and the tail is fuller. Its hooves are round instead of U-shaped. A hinny is usually smaller than a mule, and has more of the disposition of the horse parent and less of its mother's stubbornness.

The mule's voice is a variation of the bray of an ass, but it is uniquely his own. The forelock and chestnuts are, like the ass, lacking. Mules come in all colors, spotted ones now very popular. Typical coloration is still black, bay or chestnut, but the spotted varieties can range from all varieties of appaloosa to pinto.

Mules have been produced historically in the Mesopotamian region for centuries. Many were hinnies, as horses were rare, and one stallion could produce a whole herd of hinnies in the length of time a mare could produce one mule. Solomon is described in the Bible as riding a mule to Gihon, where he was appointed king over Israel. Mules have been common in most countries for at least 3000 years, and were favored as pack animals for war, long transport and for farming. There is a very long history of mules and hinnies in China, and very large mules of 16 hh are not uncommon and were traditionally bred for pulling carts, and is more common today in China than elsewhere in the world.

In Roman times, the ox was the most commonly used beast of burden, followed by the mule and the ass. Horses were divided into three categories -- the noble, the stock for breeding mules, and the common stock. The practice of separating male donkey foals (suitable for breeding to mares) from the mothers was tradition to Rome. The ass would be more easily persuaded to mate with a mare. Mules can be found in connection with royalty on Roman coins.

Breeding and management of mules has become a large industry in some countries as there has been a great demand for them as pack animals, farming and draught work. Spain was once the greatest mule producing country, and the most popular Jacks came from Spain and produced large and very powerful mules. The island of Cyprus is the last stronghold of the ass and the mule in the Mediterranean, with the hinny once very popular as a riding and pack animal. In Egypt, there were no depictions of an ass pulling a chariot, but a pair of white male hinnies are in a well known painting at a tomb in Thebes. The province of Poitou in western France has been a breeding center for very large mules, used more for agricultural work rather than as pack animals, Mules were even used in the expedition to the South Pole in 1912.

Columbus brought the first mules to America on a return trip to the New World in 1493 along with other domesticated animals. Pack trains of mules crossed America from shore to shore to supply industry and the wards. General George Washington is usually credited for being the first mule breeder in America. Mules were scarce in colonial days and Washington valued them highly. When Washington died, he is said to have had 42 working mules and 15 younger ones.

Mammoth "Warrior" was the first Catalonian Jack brought to Kentucky in 1832 by Henry Clay. He was crossed with the local jennets. A few years later a second Jack was imported -- "Mammoth." Mammoth is said to be the jackstock of this country what Messenger is to the trotting horse and what Denmark is to the saddle horse. He was not used as mule stock, but was mated to Warrior jennies. The result is the American foundation jackstock today known as Mammoth Jacks, which are used to produce very large and powerful mules.

Lewis and Clark recorded that mules commanded a higher price than horses, and had to trade nearly twice the goods for a mule as for a horse. Abraham Lincoln was "sorry to lose the mules" when he was told Confederate soldiers had captured a general and 40 mules. American ranchers would raise as many mules as they could due to the scarcity and high value of mules. Commanche Indians, when learning of the value of mules, would steal burro jacks to breed to their mares. The Commanche mule result was a small 600 pound mule of great stamina, excellent for farming, mining and mountain men's pack animals.

Mule trains frequently crossed the famous Santa Fe and Chisholm Trails, and the Chihuahua Trail was worn deep by heavy traffic of mules, oxen and burro trains. The mule was "stand-by" to pull prairie schooners when pioneers moved westward. The wagons had a capacity of 5000 to 16,000 pounds, were pulled by 6 to 8 teams of mules, and drivers were called mule- skinners or bullwhackers. General George Custer's campaign of 1868 included the longest mule train ever organized on the plains -- over 800 mule teams. The Butterfield Southern Overland Mail Stage Line used Spanish mules on most of the desert run that covered nearly half of the entire 2,759-mile 23-day route.

Buffalo Bill Cody was mounted on a little grulla Commanche mule when he met Custer to be a guide. When Custer informed Cody that they had to travel fast, Cody silent, touched his mule with his spurs and led off with the column following. By early afternoon, Cody was required to stop several times for the others to catch up, horse in a lather. By camptime, the mule was still in the lead, and Custer offered to trade his horse for the mule -- Cody rode the mule back over the same trail that night.

Teams of forty mules were hitched to wagons carrying tons of borax (a white, crystalline salt used in glass and soaps), and they pulled the heavy loads 165 miles from the Harmony Borax works across salt fields, mountains, and desert to the railroad in Mojave, California. Do you remember the little plastic kits of these mules? (I know where there are 2 of them, in the process of being restored -- scale, about HO.)

The early mules that were usually a cross of Maltese and Andalusian jacks on native horses, came to become four different types of mules. There are sugar and cotton mules, which being large and rangy, with good quality were used on sugar and cotton plantations in the South. Then the draft mules, standing to 17 hh, with a draft horse build, were used for hauling purposes, road construction and repair, roadbed construction, and lumbering. Third, are the farm mules, who were a miscellaneous lot and used for any farming task. Last were the mining mules, which came in large and small sizes depending on whether they were intended for surface mining or in pits and tunnels. The mule was especially valuable for mining, as horses were spooked by the low ceiling, whereas the mule simply folded his ears, lowered his head and went on with the task without panic.

United States Army mules were used from 1775 until 1975, when the last 136 mules were sold. The mules had been used to transport army supplies in the 19th century and during both world wars. Most people are more familiar with the draft-type mule, which is used for farm work or contest pulling. The draft mules are usually large and unsuitable for riding purposes.

Today there are four distinct types or "breeds" of mules, but they are still just called a mule. The Miniature mule is usually from Shetland pony and Miniature mares either by a standard Jack or a Miniature Jack, and is a small pony-sized mule for children to ride or for driving for adults. The Miniature stands to 50" tall. The Saddle Mule is bred specifically from riding type mares, either by Mammoth or Large Standard Jacks. The Pack and Work mule is from large work type mares by a Mammoth Jack. The Draft mule is from draft type mares by Mammoth Jacks, and is a stout mule about 16 hh or taller.

"Belling" the tail is a method of distinguishing a number of identical mules from one another. Hunks of tail are clipped in a manner to form a bell or bells stacked over each other. This system is often found used with army mules and by packers.

Mules have the qualities of both the horse and the ass that make them good animals for a numerous variety of tasks. The horse has the instinct to flee for survival in its natural plains habitat, while the donkey learned to survive in rocky, rugged terrain where hasty flight could mean death or serious injury. These qualities make the mule good saddle stock and include traits of strength and endurance, and the abilities to withstand heat and subsists on less and poorer quality food than the horse. The mule's tougher feet may never need to be shod. He is more surefooted, less likely to panic, less susceptible to disease, and as a general rule more likely to outlive a horse. A built-in mechanism (from the ass), similar to the camel's, enables the mule to drink water long enough to replace lost body fluids, avoiding founder after long, hard, hot rides. Also the mule will not eat during a hot day, preferring the evening coolness.

Often confused with stubbornness, a mule's intelligence allows him to protect himself from situations where he could be hurt, and he always saves enough energy to get home. There is an account where a man whose mule would readily lift each hoof for him to clean if it were dirty. One day, while cleaning his mule's hooves, he had no trouble with the first three, but the mule refused to lift the last hoof. After the struggle, the man had the hoof raised, and saw that it was as clean as a whistle! Mules appreciate lots of personal attention, and often will only perform to capacity when treated to their liking. A mule can harbor hard feelings to someone who abuses them, and may react at a later more opportune time.

Saddling a mule is important. Since the mule has a tendency to carry his rump higher than a that of a horse, some special breeching may be needed to keep the saddle from sliding forward over the withers, and rubbing the elbow.

Mules excel at jumping, and have been outlawed from the ring because they have outdone the horse. A mule show would not be complete without the "Coon Hunter's Mule Jump." Originating from a nighttime raccoon hunt where the mule carries the hunter after the hounds, the mules jumps obstacles from a standing start after the hunter dismounts. More mules are showing up on trail rides and at rodeos, indicating a return to popularity.

Today a mule's lineage is as carefully controlled as that of a blood horse. The U.S. Dressage Federation now allows mules to piaffe and passage alongside their Thoroughbred and Trakehner cousins, after much convincing of the well-bred mule's competitive abilities and appearance. Mules have played prominent roles in our history and have a host of virtues. Mules are often the unsung heroes in great historical events.

For more information about mules, write to: The American Donkey and Mule Society, Inc., 2901 North Elm Street, Denton, TX 76201.

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Published December 1994 in NorthWest Breyer Horse Club Newsletter. (em)

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