Horses, donkeys and mules and their utility

Most horses perform work such as carrying humans on their backs or are harnessed to pull objects such as carts or plows. However, hundreds of distinct horse breeds were developed, allowing horses to be specialized for certain tasks; lighter horses for racing or riding, heavier horses for farming and other tasks requiring pulling power. Some horses, such as the miniature horse, can be kept as pets. In some societies, horses are a source of food, both meat and milk; in others it is taboo to consume these products. In industrialized countries, horses are predominantly kept for leisure and sporting pursuits, while in other parts of the world they are used as working animals.

Because horses and humans have lived and worked together for thousands of years, an extensive specialized vocabulary has arisen to describe virtually every horse behavioral and anatomical characteristic with a high degree of precision.

The English-speaking world measures the height of horses in hands, abbreviated "h" or "hh," and is measured at the highest point of an animal's withers. One hand is 4 inches, or 10.16 cm. Intermediate heights are defined by hands and inches, rounding to the lower measurement in hands, followed by a decimal point and the number of additional inches between 1 and 3. Thus a horse described as 15.2 hh tall, means it is 15 hands, 2 inches, or 62 inches/1.57 m in height.

The size of horses varies by breed, but can also be influenced by nutrition. The general rule for cutoff in height between what is considered a horse and a pony at maturity is 14.2 hands (147 cm, 58 inches) as measured at the withers. An animal 14.2h or over is usually considered a horse and one less than 14.2h is a pony.

However, there are exceptions to the general rule. Some smaller horse breeds who typically produce individual horses both under and over 14.2h are considered "horses" regardless of height. Likewise, some pony breeds, such as the Pony of the Americas or the Welsh pony, share some features of horses and individual animals may occasionally mature at over 14.2h, but are still considered ponies.

The difference between a horse and pony is not simply a height difference, but also a difference in phenotype or appearance. There are noticeable differences in conformation and temperament. Ponies often exhibit thicker manes, tails and overall coat. They also have proportionally shorter legs, wider barrels, heavier bone, shorter and thicker necks, and short heads with broad foreheads. They often have calmer temperaments than horses and also a high level of equine intelligence that may or may not be used to cooperate with human handlers.

Light riding horses such as Arabians, Morgans, or Quarter Horses usually range in height from 14.0 (142 cm) to 16.0 hands (163 cm) and can weigh from 386 kilograms to about 540 kg (850 to 1200 lb). Larger riding horses such as Thoroughbreds, American Saddlebreds or Warmbloods usually start at about 15.2 hands (157 cm) and often are as tall as 17 hands (172 cm), weighing from 500 kg to 680 kg (1100 lb to 1500 lb). Heavy or draft horses such as the Clydesdale, Belgian, Percheron, and Shire are usually at least 16.0 (163 cm) to 18.0 hands (183 cm) high and can weigh from about 680 kg up to about 900 kg (1500 lb to 2000 lb). While ponies cannot be taller than 14.2h (147 cm), they may be much smaller, down to the Shetland pony at around 10 hands (102 cm), and the Falabella which can be no taller than 32 inches (78 cm), the size of a medium-sized dog. However, while many miniature horse breeds are small as or smaller than a shetland pony, because they are bred to have a horse phenotype (appearance), their breeders and registries classify them as very small horses rather than ponies.

The largest horse in (recorded) history was a Shire horse named Sampson, later renamed Mammoth, foaled in 1846 in Bedfordshire, England. He stood 21.2½ hands high (i.e. 7 ft 2½ in or 2.20 m ), and his peak weight was estimated at over 3,300 lb (approx 1.5 tonnes). The current record holder for the world's smallest horse is Thumbelina, a fully mature miniature horse affected by dwarfism. She is 17 inches tall and weighs 60 pounds.

The International Museum of the Horse

Slideshow : Beautiful horses

The Donkey

Donkeys, zebras and mules all differ somewhat from horses in conformation. The most noticeable difference is of course the ears. Donkeys' ears are MUCH longer in proportion to their size than a horse's. The necks are characteristically straighter in the longears, and most donkeys and all zebras lack a true wither. The croup and rump are also a different shape in the donkey and its hybrids, lacking the double-curve muscled haunch. The back is straighter due to the lack of withers. Dipped loins or severely swayed backs are a conformation fault, unless in old animals or brood jennies who have produced many foals, and not due to genetic factors.

What do mules look like?

The mule proper is said to have the body of a horse with the extremities of a donkey. The most noticeable points are its long ears, short thin mane, which may stand upright like a donkey's or be a little longer and flop over, and a tail which has shortish hairs on the dock a little longer than the donkey's but also has long hairs like the horse's, and is much fuller than the donkey's. The withers are low or non-existent, the back flat with a goose rump, the body flat-sided with weaker quarters than the horse, and also narrower and less deep-shouldered. The legs are, like the donkey's, straight, with small, hard, dense, upright, straight-sided hooves. The head is a little narrower than the donkey's, but otherwise very similar, except for the eyes, which are specifically mule - but difficult to describe.

The hinny generally has the body of a donkey with the extremities of the horse. The ears are shorter than a mule's, the mane and tail longer and thicker, the legs stronger with hooves which are rounder and less upright, the body rounder and deeper, and the head shorter and narrower. The most common coat colour is blue-grey roan. However, it is noticeable that hinnies differ far more from each other than do mules, with every imaginable variation, from being almost indistinguishable from a horse, through being mule-like, to being almost indistinguishable from a donkey.

Advantages of mules

Mules, having hybrid vigour, can grow taller than both parents. Weight for weight they are stronger than horses, and are much longer-lived with much longer working lives, although maturing slightly later. They rarely become ill or lame or suffer wounds, can withstand extremes of temperature, can live on frugal rations, have tremendous stamina and resilience and are exceptionally sure-footed.

Hinnies are said to lack hybrid vigour, and it has always been recognised that they are smaller than mules (although this may partly be due to their being carried in a smaller womb), less strong and with less stamina and hardiness.

Mules' temperament

Mules have a reputation for being obstinate and bad-tempered, but as with donkeys, the mule's legendary stubbornness is in fact a manifestation of its talent for self-preservation. There are times when a human finds this 'talent' annoying, when he is disobeyed by a mule, but there are many other times when it can be a great advantage: if a mule takes care of itself, then it follows that it is also taking great care of its cargo, human or otherwise. It is not for nothing that mules are chosen rather than horses to take tourists down the Grand Canyon! By intelligent handling, it is quite possible to foresee occasions on which a mule is likely to be 'stubborn' and to avoid them.

The undeserved reputation for bad temper is, I believe, due to the mule's unexpectedly sensitive and untrusting nature. Until he has learnt to trust a person, he is worried that the person may do him harm, and will take defensive action (never offensive) by kicking them, should he feel the occasion merits it. And mules are splendid kickers - they kick fast and accurately, and if a mule misses, it is because he intended to. Unfortunately many of the people who have worked with mules over the centuries have not appreciated this sensitivity, and have not understood another characteristic of the mule: that you cannot force him to do anything, but must persuade him, or organise his work so that he is only asked to do those things which he will want to do. Failure to appreciate this has led to many a battle between man and mule, and to the mule's bad reputation.

Mules are highly intelligent - mule devotees would say more intelligent than horses - and are very quick to learn, with a grasp of a situation which often seems little short of miraculous. This means that their handlers need to be quick-witted to stay one jump ahead of them. A well-trained and handled mule is obliging, kind, patient, persevering, calm, tolerant, sensible, loyal, affectionate, playful - and also proud, jealous and calculating. Being so intelligent, a badly trained and handled mule can be a problem.

Hinnies tend to be more donkey-like in temperament, which may be partly due to the fact that they were reared by donkeys, although this is unlikely to be the whole of the story. They are generally quieter, more compliant, less curious, less adventurous and less independent than mules. Being less sensitive and untrusting, they are less likely to kick, preferring to avoid trouble rather than confront it. Despite their reputation for being less useful than mules, there are many examples of their being much appreciated.