Domesticated thousands of years ago by frankincense traders, who trained the gangly cud-chewer to make the long and arduous journey from southern Arabia to the northern regions of the Levant the camel became the desert dweller's primary source of transport, shade, milk, meat, wool and hides.

Fossil remains indicate that the camel family originated in North America. It is believed that ancestors of the modern camel lived in North America at least 40 million years ago, wandered across the Alaskan 'land bridge' to Asia and eventually Africa. In Asia, two groups became separated and adapted to their various climates to become the two main types known today as the one-humped dromedary and the two-humped, shorter-legged Bactrian camel.

Camels are domesticated only in Africa and Asia. Even today the Bedouin are not as dependent on the camel as they once were. These days, camels are valued more as thoroughbred racing animals and sentimental images of the past than as the mainstay of transportation. But in many parts of Africa and Asia, camels still pull ploughs, turn waterwheels and transport people and goods to market along desert routes unpassable by wheeled vehicles and are often relied on for milk as the only source of food.

The camel�s behavior is unpredictable at best. Camels have the reputation of being bad-tempered and obstinate creatures that spit and kick. In reality, they tend to be good-tempered, patient and intelligent. The moaning and bawling sound they make when they're loaded up and have to rise to their feet is like the grunting and heavy breathing of a weight-lifter in action, not a sign of displeasure at having to work. Thick callus-like bare spots of dry skin appear on a camel's chest and knee joints when the animal reaches five months of age. These leathery patches help the camel lie on the hot sand and raise the body slightly, creating shade and space under the body.

A fully-grown adult camel stands 1.85m at the shoulder and 2.15 m at the hump and can weigh up to 1000 kg. The rope-like tail is over 50cm long.

Camels do not pant, and they perspire very little. Humans start to sweat when the outside temperature rises above the normal body temperature of 370C, but the camel has a unique body thermostat. Its body temperature fluctuates over 60C between the cold desert mornings and hot daytime temperatures, thereby conserving body fluids by avoiding unnecessary water loss. Of the many adaptive mechanisms that enable the camel to withstand the severity of the desert climate, hematology is one of the most interesting. The hematocrit is around 28% (as opposed to 45% in most mammals), thus providing a large reservoir of water. The oval erythrocytes can withstand extreme changes of osmolality: Crenation is not complete at concentrations of 20% saline (almost five times the concentration of sea water) and no full hemolysis in 0.1% saline solutions (almost distilled water). This allows for large concentration of salts in the blood circulation or the loss of much water without crenation and the ability to imbibe vast amounts of water without hemolysis occurring. After drinking these large amounts of water the erythrocytes become rounded. In addition, camelid blood contains large numbers of cells (polycytemia), which enable the llama to acquire ample oxygen in the heights of the Andes and allow the desert camel to reduce its respiratory rate thereby leading to reduce losses of respiratory water.

Camels need very little water if their regular diet contains good, moisture-rich pasture. When camels withstand severe dehydration of over 2 weeks and losing a third or more of their body weight, a large animal can drink as much as 200 litres in three minutes. Such an amount would kill another mammal, but the camel's unique metabolism enables it to store the water in its cardiovascular system.

The mouth is large with 34 sharp teeth. They enable the animal to eat rough thorny bushes without damaging the lining of the mouth, and can be used as biting weapons against predators if need be. A camel gulps down its food without chewing it first, later regurgitating the undigested food and chewing it as cud. Large muscular nostrils that can be opened and closed voluntarily protect the nasal passages. Normally the nose is a thin split. When a camel twitches its nose, it is cooling the incoming air and condensing moisture from its outgoing breath.

Camels come in every shade of brown, from cream to almost black. White camels are especially valued. The ears are small, but its hearing is acute. They are lined with fur to filter out sand and dust blown into the ear canal. The eyes are large, giving a soft, doe-like expression. They are protected by a double row of long curly eyelashes that also help keep out sand and dust, while thick bushy eyebrows shield the eyes from the desert sun. All camels moult in spring and will grow a new coat by autumn. Camel hair is used to make traditional Bedouin rugs and tents. A camel can shed as much as 2.25 kg of hair at each moult.

The long, thin legs have powerful muscles that allow the animal to carry heavy loads over long distances. A camel can carry as much as 450 kg, but a usual and more comfortable cargo weight is 150 kgs. It is normal for a camel to work as a beast of burden for only six to eight months of the year; the remainder of the time it needs to rest and recuperate. The normal 'amble speed' for a walking camel is 5kph; a working camel will typically cover 40km a day. Racing camels can reach 20kph at the gallop. The feet of the camel are broad, flat, leathery pads with two toes on each foot. When the camel places its foot on the ground the pads spread to prevent the foot from sinking into the sand. When walking, the camel moves both feet of one side of its body, then both feet on the other. This gait suggests the rolling motion of a boat, explaining its 'ship of the desert' nickname.

A camel can go for more than 14 days with little or no food, and can lose a quarter of its body weight without impairing its normal functions. These days, camels rely on man for their preferred food of dates, grass and grains such as wheat and oats, but a working camel traveling across an area where food is scarce can easily survive on thorny scrub or whatever else it can find - bones, seeds, dried leaves, or even its owner's tent!

Contrary to popular belief, a camel does not store water in its hump. It is a mound of fatty tissue from which the animal draws energy when food is scarce. When a camel uses its hump fat for sustenance, the hump becomes flabby and virtually disappears. Food and a few days' rest will return the hump to its normal firm condition.

After a gestation periods of 13 months, a camel cow usually bears a single calf, never twins. The calves walk within hours of birth, but remain close to their mothers until they reach maturity at five years of age. They retire from active duty at 25, but may live up to 40 - 50 years.

The camel as a source of food: The best camel meat is from young males. It is regarded as a delicacy in the Arabian diet, and is gaining popularity in arid lands where it is difficult to herd sheep, cattle and goats and even in Australia where it is as popular as meat. The meat of young animals is tasty and not unlike beef. Camel's milk is much more nutritious than that of the cow. It is lower in fat, the lactose is easily digested, even by those with lactase deficiency, and higher in potassium, iron and vitamin C. It is normally drunk fresh, and the warm frothy liquid, heavy and sweet, is usually an acquired taste for the Western palate. Most Saudi Arabian camels are females reared in dairy herds for their milk which is nowadays used to treat a variety of illnesses, as well as for making delicious ice-cream, bringing the camel back into economic focus.

ISRAEL JOURNAL OF

VETERINARY MEDICINE home archive journal

Volume 58 - No. 2-3 - 2003

Table of contents

INSTRUCTIONS FOR AUTHORS

Camel (Camelus dromedarius)