What makes a mule different from a horse?

First, let's clarify what a mule is. A mule is the offspring of a male donkey (a jack) and a female horse (a mare). A horse has 64 chromosomes, and a donkey has 62. The mule ends up with 63. Mules can be either male or female, but because of the odd number of chromosomes, they can't reproduce. However, a male mule should be gelded in order to make him a safe and sociable animal.

Except for the long ears, mules look very similar to horses, but their muscle composition is different. Mules have smoother muscles than horses. Think of a football player’s muscle build compared to that of a ballerina. Both are very strong, but the mule has greater physical strength for his size, and more endurance. A mule gets its athletic ability from the horse and its intelligence from the donkey. Donkeys and mules have been labeled "stubborn" for centuries, but it is really only an abundance of common sense and a strong desire for self-preservation that might make them inclined to resist. Mules and donkeys actually have a natural attraction to humans. When treated with patience, kindness and understanding, they learn to trust and obey. If they are treated with force and abuse, they are not likely to comply with your wishes. If only a mule could talk, most people would be surprised by how smart they really are!

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The word “mule” can be used for any hybrid and is a cross between two species of equine: the horse or pony (Equus caballus) and the domestic donkey (Equua asinus). The term “mule” is used for either the cross of male donkey on female horse or the cross of female donkey on male horse, although the latter cross is more correctly known as a “hinny.” Mules and hinnies each have one horse and one donkey parent, however the two crosses generally differ from each other in appearance and stature and, to some extent, temperament.

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In addition to being the father of our country, George Washington was an enlightened agriculturalist—a visionary who, early on, saw the true value of the mule. But right from the beginning, he faced a major obstacle. At the time, the Spanish Government prohibited acquisition of the legendary Catalonian donkey. However, in 1785, King Charles III of Spain presented Washington with a gift of two jacks and two jennets. One of the jacks died during the voyage, but the survivor, named Royal Gift, went on to sire an American dynasty that reshaped the very landscape of this country. By the early 1900s the mule population in this country had exploded to nearly 6 million. But with the advent of engine-powered vehicles, the mule’s once-critical role in agriculture and industry diminished. It’s estimated that by the late 1960s, fewer than 10,000 mules existed in the U.S., and many of those languished—unused, unnoticed and in danger of fading from our culture altogether.

But a handful of mule and donkey lovers were determined to keep that from happening. Among them were Paul and Betsy Hutchins who, in 1967, founded the American Donkey and Mule Society, an organization dedicated to the protection and understanding of longears. They also publish The Brayer, a bi-monthly magazine with an international subscriber base. Mules and donkeys have enjoyed resurgent popularity during the last 40 years. Today, annual events such as Bishop Mule Days in Bishop, Calif., host more 30,000 people and 700 mules. Mule events, stock shows, trade publications and even television programs like Meredith’s series, Training Mules and Donkeys, airing on RFD-TV, continue to foster interest in these amazing animals.

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• 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

Division by size rather than breed is due to unclear ancestry in the New World. Donkeys were turned loose by explorers and interbred.

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Today, donkeys and mules are registered with several different registries, the largest being the American Donkey and Mule Society. Other registries include the American Mule Association and Standard Jack and Jennet Registry.

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What are mules and hinnies?

The mule is a hybrid cross between a male donkey called a jack and a female horse, or mare. Because he most often demonstrates the best traits from each parent, he possesses what we call hybrid vigor. The mule inherits from the donkey his incredible strength, intelligence, patience, perseverence, endurance and surefootedness from the jack and his equine beauty, athletic ability and speed from the horse.

The hinny, or hinney, is also called a mule. However, the hinny is the hybrid cross between a male horse, or stallion, and a female donkey called a jenny, or jennet. The hinny is different from a mule in very subtle ways. For instance, the hinny is a somewhat slower and more meticulous mover than the mule. He inherits his way of going from the jennet as does the mule that tends to be a little faster, more energetic and more agile like the mare. The hinny, because of his meticulous way of going is actually better in very steep, rocky terrain and especially in loose rock and will not tire as quickly as a mule. Gaited hinnies are preferable in this kind of terrain where there is little opportunity to gallop because they have a smooth, more ground covering gait.

The hooves of a hinny tend to be more donkey-like, narrow, oval and more upright where the hooves of a mule will look more horse-like, a little more round (though still oval), with slightly more angle than the donkey hoof, but not as flat, round and angled as the horse’s hoof. On both hinnies and mules, the hooves should be trimmed more upright and the heels should be left longer than that of the horse.

The hinny will also eat more different kinds of shrubs and bushes to sustain himself where a mule will be more selective, again because of the influence of the female parent which makes the hinny more desirable to those living in remote mountain areas with little vegetation.

Both the mule and the hinny have more endurance than the horse by far and are more resistant to parasites and disease, require less feed for good health, have tougher hooves than the horse and have an incredible sense of self preservation that keeps them safe which is often mistaken for stubbornness. The horse has a flight reflex when startled and the donkey has a freeze reflex; mules and hinnies can exhibit both the freeze and flight reflexes depending on their own unique personalities and the situation at hand.

When breeding for mules, since the jacks are generally smaller and of slighter build than a horse, mule foals are generally smaller than horse foals and the mare has very little problem foaling.  When breeding for hinnies, one needs to be cautious as the jennets are smaller and of more slight build than mares. A large stallion could produce a foal that would be too large and difficult for the jennet to foal easily. Matching the size of the parents is much more important with hinnies. It is more difficult for a jennet to settle after being bred to a stallion than it is for a mare to settle after being bred by a jack, so breeding for hinnies can take significantly longer.

• Donkey + zebra = Zebrass or Zedonk
• Horse + zebra = Zorse, or if pony dam, Zony
• 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 and looks very much like a mule. The hinny has been used as a saddle animal from antiquity and is more difficult to produce than the mule, because the jennet does not conceive well with the stallion.
• Certain breeds of mares do not conceive as well as others with the jack
• Although hybrids are typically sterile, two documented cases of fertility do exist. One was known as Old Beck and the other as Krause.
• Mules are also used for embryo transplant.
• There are no documented cases involving sterile male mules.

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• A distinctive bray.
• Long ears.
• Short, upright and thin mane.
• Hair only on the end of its tail.
• Tends to look more horse-like.
• May come in variety of colors.
• Hoofs are narrow and box-like, unlike the horse’s hoof. They’re upstanding, and made for rock and mountain climbing. They are tough and elastic, non-chipping and can grow to long lengths when the animal is on soft ground and they’re left untrimmed.
• Long body with long, wiry muscles.
• Short and straight back. Lacks upstanding withers and is excellent for packing and weight bearing.
• Bone is dense and hard.
• Gestation is 12 months, whereas the gestation period for a horse is 11 months.
• Usually has a white belly, muzzle and circles around the eyes.
• Colors are much like that of a horse.
• They can come in more colors than a horse, even an Appaloosa.
• Mule's conformation falls somewhere in between that of the donkey and that of the horse.
• Mules inherit best from both its sire and its dam
• Mules get their athletic ability from the horse., while strength and intelligence come from the donkey.

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• Highly intelligent, alert, curious and affectionate when not worn down by bad conditions, i.e., cruel treatment, bad shelter, bad food and water, or overwork.
• Quick to learn. A well-trained mule is calm, tolerant, loyal, affectionate, obliging and patient.
  Sensitive. Mules and donkeys might be mistaken for stubborn when they’re actually afraid or confused.
• Has common sense and not prone to panic or carelessness
• Can recognize danger.

According to Tom Constantino, "Jesus chose a donkey colt, unridden, uninfluenced by man, for his triumphant entry into Jerusalem on Palm Sunday. In doing so, He recognized the donkey's instinctive role of servitudes to man and God. Time and time again since the beginning of recorded history, the donkey has proved its quality of character. Its noble instincts are special. It was not created to be hunted for food or sport, and it has no natural enemies. It is the duty of the world to understand the true depth of the donkey, and to care for this noble creature."

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