Dromedary: Difference between revisions

Dromedary camel
Conservation status
Domesticated
Scientific classification
Missing taxonomy template (fix):	Camelus dromedarius
Binomial name
Camelus dromedarius Linnaeus, 1758
Domestic dromedary range
Synonyms
Species synonymy[1] *Camelus aegyptiacus Kolenati, 1847 *Camelus africanus Gloger, 1841 *Camelus arabicus Desmoulins, 1823 *Camelus dromas Pallas, 1811 *Camelus dromos Kerr, 1792 *Camelus ferus Falk,1786 *Camelus lukius Kolenati, 1847 *Camelus polytrichus Kolenati, 1847 *Camelus turcomanichus J. Fischer, 1829 *Camelus vulgaris Kolenati, 1847

The dromedary camel (pronounced /ˈdrɑmədɛɹi/ or /ˈdrɒmədri/) or Arabian camel (Camelus dromedarius) is a large, even-toed ungulate with one hump on its back. It was first described by Carl Linnaeus in 1758. The dromedary camel is the second largest member of the camel family after the larger Bactrian camel.

It feeds on foliage, dry grasses and desert vegetation. The camels are active in the day, and rest together in groups. Herds can consist of about 20 individuals. It shows no signs of territoriality, as herds often merge during calamities. They have various adaptations to help them exist in their desert habitat. Mating may occur in winter, but is peak in the rainy season.

Its native range is unclear, but it was in probably the Arabian Peninsula, where it was domesticated about 4000 years ago. The domesticated form occurs widely in North Africa, South Asia and the Middle East.^[1] The world's only population of dromedaries exhibiting wild behavior is an introduced feral population in Australia.^[2]

The scientific name of the dromedary camel is Camelus dromedarius, which could be based on the Greek δρομάς δραμεῖν (dromas kamelos), meaning 'running camel'.^[3] The Babylonians and Assyrians were the first to refer to the dromedary as gammalu, similar to the word gâmâl used in the Bible.^[4]

The term 'dromedary' comes from the Old French word dromedaire, or the Latin word dromedarius, which means 'swift'. It is based on the Greek word dromas, the prefix 'dromad-' meaning runner.^[5] An early variant of this word was 'drumblediary' (used in the 1560s).^[6] The term 'camel' is derived via Latin and Greek from Hebrew or Phoenician gāmāl, possibly from a verb root meaning 'to bear/carry' (related to Arabic jamala).^[7] It may also have an Old French origin from the word chamel and Modern French chameau.^[8]

The dromedary was first described by Carl Linnaeus, a Swedish botanist, physician, and zoologist, in 1758. It is a member of the genus Camelus and the family Camelidae.^[1] British veterinarian Arnold Leese had classified dromedaries on the basis of their habitat into three groups: hill camels, plains camels and intermediate between the former two.^[9] Earlier the dromedary and Bactrian camel were considered the same species, but this was corrected by Macedonian philosopher Aristotle, who defined them as one-humped and two-humped in his book History of Animals.^[4] But today, as both the species interbreed successfully, some authors have considered merging them into one species with two varieties on the basis of hybrid fertility.^[9] However, there is 10.3% of difference between the species found in a mitochondrial analysis. There are also indications that the onset of speciation in Camelus started in the early Pliocene.^[10]

The dromedary camel has 74 chromosomes, the same as other camelids. No karyotypic differences exist among the camels.^[9] The autosomes consist of five pairs of small to medium-sized metacentrics and submetacentrics, in which the X chromosome is the largest. There are 31 pairs of acrocentrics.^[11]

The origin of camel hybridization dates back to as early as the 1st millennium BCE.^[12] Many hybrids have been formed with the dromedary. An alpaca crossed with a female dromedary produced a stillborn full-term fetus.^[13] In a study, female dromedaries were inseminated with guanaco semen. Two conceived and one female fetus was aborted, while another female fetus was stillborn. Similarly, female guanacos were inseminated with camel semen. Six were conceived but other than one born prematurely, no fetus remained alive. This fetus bore similarities to both a camel and a guanaco.^[14]

For about 1000 years Bactrian and dromedary camels have been successfully bred to form hybrids with a long hump slightly indented to a side or a small and a large hump. These hybrids have more strength and size compared to their parents - they can bear more load and thus are more useful.^[11][12] A cross between first-generation female hybrid and a male Bactrian camel also produces a useful hybrid. Other types of hybrids are bad-tempered or runts.^[11]

The oldest and also the smallest known camel, Protylopus, occurred in the upper Eocene in North America. In the transitional period from Pliocene to Pleistocene, the Camelus species migrated across the Bering Strait and dispersed widely to Asia, eastern Europe and Africa.^[11] By the Pleistocene, ancestors of the dromedary came to be known from the Middle East and North Africa.^[15]

The ancient fossils of C. sivalensis and C. antiquus have been traced in the Shiwalik Hills in India. Fossils of subgenus Paracamelus were found in western Siberia, China, near the Sea of Azov and the northern coast of the Black Sea. In the Pliocene, Camelus species ranged much far south in Africa, and in the northern area remains of C. thomasi have been found. The dromedary has a possible origin from Arabia, hence its name Arabian camel. A jawbone of a dromedary was found from the southern Red Sea coast of Saudi Arabia, whose radiocarbon date was 8200 BP, and calibrated date was 7100-7200 BC.^[16][17]

As implied by the Book of Genesis, the dromedary camels were used by nomadic tribes in the second millennium BCE, but the book was composed at a later time, and the information can not be taken as true.^[4] Scholars have dated the spread of dromedaries to the first centuries AD, and evidently before the arrival of the Romans.^[18] The Persian invasion of Egypt under Cambyses in 525 BC introduced domesticated camels to the area. The Persian camels, however, were not particularly suited to trading or travel over the Sahara; rare journeys made across the desert were made on chariots pulled by horses.^[19]

These camels became common after the Islamic conquest of North Africa. While the invasion was accomplished largely on horseback, the new links to the Middle East allowed camels to be imported en masse. These camels were well-suited to long desert journeys and could carry a great deal of cargo, allowing substantial trade over the Sahara for the first time.^[20][21] In Libya they were used for transportation within the country and their milk and meat constituted the local diet.^[22]

In the mid-seventh century, the dromedary was first used in warfare when Achaemenid king Cyrus the Great made use of these animals while fighting with king Croesus of Lydia in 547 CE. Since then the Persians , Seleucideans, Alexander the Great, Parthians and Sasanians also used dromedaries in warfare. They were also used in the eastern provinces of Egypt, Arabia, Judaea, Syria, Cappadocia, and Mesopotamia.^[4]

In 1840, six camels were shipped from Tenerife to Adelaide, but only one survived the trip, arriving on October 12, 1840. Numerous camels were imported into Australia between 1840 and 1907 to open up the arid areas of central and western Australia, and were used mainly for riding and transportation.^[23] The explorer John Horrocks was among the first to use camels to explore the arid interior of Australia during the 1840s. About a million feral camels are estimated to live in Australia,^[23] descendants of domesticated camels that were released or ran away on their own.

Dromedaries were first domesticated in central or southern Arabia. Experts believe it happened around 4000 years ago in the Arabian peninsula.^[24][25] It was only in the ninth or tenth millennium BCE when the animal became popular in the Near East. Today there are almost 13 million domesticated dromedaries, found mainly in the area from Western India via Pakistan through Iran to northern Africa. No dromedaries survive in the wild in their original range, although the escaped population of Australian feral camels is estimated to number at least 300,000.^[26]

The skeleton structure of a dromedary

Dromedary body for comparison with skeleton

The dromedary camel is one of the two largest living camels, along with the Bactrian camel. Adult male dromedaries grow to a height of 1.8–2 m (5.9–6.6 ft) and females to 1.7–1.9 m (5.6–6.2 ft). The weight is usually in the range of 400–600 kg (880–1,320 lb) for males, with females being 10% lighter. Large males can weigh as much as 1,000 kg (2,200 lb).^[27]

Their coats can range from black to a much lighter color, and hair is concentrated more on neck, hump and shoulder. Male dromedaries have a soft palate, which they inflate to produce a deep pink sack, which is often mistaken for a tongue, called a doula in Arabic, hanging out of the sides of their mouths to attract females during the mating season. Dromedaries are also noted for their thick eyelashes. The dromedary has two toes on each foot, appearing like flat, leathery pads. The hump is of fat bound together by fibrous tissue. It can be 20 cm (7.9 in) or more.^[11] Unlike many other animals, camels move both legs on one side of the body at the same time. They show remarkable adaptability in body temperature, from 34°C to 41.7°C,. This is an adaptation to conserve water.^[2] The dromedary camel exhibits sexual dimorphism, as both the sexes are much different in their appearances.^[2] They have sharp eyes and good sense of smell.^[17]

The dromedary differs from the Lama species due to its hump and a shoulder height of above 170 cm (67 in). It has smaller, round ears, almost square feet and a long, tufted tail. It has four mammary glands while the Lama species have two, and while dromedaries have three upper premolars Lama species have two. The cranium has a well-composed sagittal crest, long facial part and an indented nasal bone.^[11] They have an average lifespan of 40 years,^[27] which can be extended to 50 years under captivity.^[2]

The dromedary have 22 milk teeth, which are eventually replaced by 34 permanent teeth.^[28] The lenses of their eyes contain crystallin, which constitutes 8-13% of the total protein present there.^[29] The epidermis is 0.038–0.064 mm (0.0015–0.0025 in) thick, and the dermis is 2.2–4.7 mm (0.087–0.185 in) thick. Though face glands are absent, males have occipital glands 5–6 cm (2.0–2.4 in) below the neck crest, on either side of the midline of the neck. They seem to be modified apocrine sweat glands which secrete a smelly coffee-colored fluid during rut. The mammary glands, four-chambered and cone-shaped, are 2.4 cm (0.94 in) in length and 1.5 cm (0.59 in)in diameter at the base. They can continue to lactate even during dehydration, water content exceeding 90%.^[11]

The heart is 5 kg (11 lb) in weight, and has two ventricles with the apex curving to left. Their pulse rate is 50 beats per minute, and normal blood pressure 6 to 115 mmHg. The normal blood volume is 0.093 L (0.025 US gal). The lungs are not lobed, and a dehydrated camel has less breathing rate. The kidneys each have a volume of 858 cubic centimeters, and can produce urine with chloride concentrations. It is the only mammal that has oval red blood corpuscles and lacks a gall bladder. The liver is four-lobed and triangular. It has dimensions of Template:Convert/3 and a mass of 6.5 kg (14 lb). The spinal cord is an average of 213.6 cm (84.1 in) long, ending at the 2nd and 3rd sacral vertebrae.^[11]

The ovaries, present in females, are reddish in color, circular and flattened. They are enclosed in a conical bursa, and have a size of Template:Convert/3during anestrus. The oviducts are 25–28 cm (9.8–11.0 in)in length. The uterus is bicornuate. The vagina is 3–3.5 cm (1.2–1.4 in) in length. The vulva is 3–5 cm (1.2–2.0 in) deep and contains a small clitoris. Placenta is diffuse and epitheliochorial with a crescent-like chorion. The scrotum, present in males, is present high in the perineum with testicles in separate sacs. Testicles are 7–10 cm (2.8–3.9 in) long, 4.5 cm (1.8 in) deep and 5 cm (2.0 in) in width. The right testicle is often smaller than the left one.^[28] During the rut, the mass of both testicles ranges from 165–253 g (0.364–0.558 lb), otherwise it is less than 140 g (0.31 lb). The prostate gland is dark yellow, usually disc-shaped and bilobate. The Cowper's gland is white, shaped like an almond and lacks seminal vesicles. The penis is covered by a triangular sheath opening backwards, and is about 60 cm (24 in) long.^[11]

Dromedary is prone to trypanosomiasis, a parasitic disease caused by Trypanosoma evansi, T. brucei, T. congolense and T. simiae. It is transmitted by Glossinaand Tabinidae species. The main symptoms are recurring fever, anemia and weakness, which usually ends with the camel's death.^[11] Brucellosis is another disease of dromedaries. In an observation, the seroprevalence of the disease was usually low (2-5%) in nomadic or extensively kept dromedaries, while it was high (8-15%) in those kept intensively or semi-intensively. Brucellosis is caused by different biotypes of Brucella abortus and Brucella melitensis.^[30]

In a study of 1039 camels in 33 herds in central Somalia, T. evansi was a prevalent parasite (1.7%-56.4% in blood smears). A total of 2.2% of the camels tested positive for brucellosis.^[31] Other internal parasites include Fasciola gigantica (a trematode), Echinococcus polymorphous and Taenia marginata (two cestodes), Trichuris, Nematodirus, Strongyloides, Haemonchus and Onchocerca (nematodes). Among external parasites, Sarcoptes species cause sarcoptic mange.^[11] In a study in Jordan, 83% of the 32 camels tested positive for sarcoptic mange, and 33% of the 257 examined specimens were seroprevalent for trypanosomiasis.^[32] In another study, following the rinderpest outbreak in Ethiopia, it was found that dromedaries have natural antibodies against rinderpest virus and peste des petits ruminants virus (ovine rinderpest).^[33]

The flea Vermipsylla alakurt and ticks like Rhipicephalus, Amblyomma and Hyalomma species cause physical irritations. Larvae of Cephalopsis titillator can cause brain compression, nervous disorders and even death. Illnesses that can affect dromedary productivity are: pyogenic diseases and wound infections due to Corynebacterium and Streptococcus; pulmonary disorders caused by Pasteurella (like hemorrhagic septicemia) and Rickettsia; camelpox due to an oriole virus; anthrax due to Bacillus anthracis; and cutaneous skin necrosis due to Steptothrixspecies and salt deficiency in diet.^[11]

In a study in Egypt, 2545 ticks (1491 adults and 1054 nymphs) were collected from dromedaries. The range of the number of ticks per camel was much broad (6 to 173). Hyalomma dromedarii was predominant, 95.6% of the adult ticks were this species. Other ticks found were H. marginatum subspecies and H. anatolicum excavatum. All nymphs were Hyalomma species. In Israel, the number of ticks per camel ranged from 20 to 105. Here, nine camels in the date palm plantations in Arava valley were injected with ivermectin, but it was not effective against Hyalomma tick infestations.^[34]

In summers, the dromedaries, usually diurnal, rest together in closely packed groups. Generally herds consist of about 20 individuals, led by a dominant male and consisting of several females. Females also lead in turns.^[11] Some males either form bachelor groups or roam alone. Groups are not territorial, and form herds of over hundreds of animals, joining other herds during natural calamities and when searching for water.^[27] During the breeding season males become very aggressive, sometimes snapping each other and wrestling, while defending the females with them. The male declares his success in the fight with the rival's head between his legs and body. Dromedaries have a reputation for being bad-tempered and obstinate creatures that spit and kick. Free-ranging camels face the large predators typical of their regional distribution, which include wolves, lions, tigers, and humans. Camels are often injured by moving vehicles.^[35]

Some special behavioral features of the camel include snapping each other without biting, showing displeasure by stamping its feet and running and occasionally vomiting cud when hurt or excited. They prefer walking in a single file. Camels find comfort in scratching parts of their body with their front or hind legs or with their lower incisors. They are also seen rubbing against tree bark and rolling in the sand. The main vocalizations include a sheep-like bleat used to locate individuals and the breeding gurgle of males, while a whistling noise is produced as a threat noise by males by grinding the teeth together.^[2] They are not usually aggressive, except the rutting males. The males of the herd disallow their females from interaction with other bachelor males, by standing or walking between them and driving them away. They seem to remember their homes, females particularly remember the place they first suckled their offspring or gave birth to it. They do not defecate with any special posture, and marking behavior is not usual.^[11]

In a study it was found that androgen levels in the blood of males controlled their behavior. In between January to April, when these levels went high, they became quite unmanageable, blew-out a palatal flap from the mouth, vocalized, and threw urine over their backs with their tails.^[36]

The diet of the camel mostly consists of foliage, dry grasses and available desert vegetation. Mostly thorny plants occur in its natural habitat.^[37] These compose 70% of their diet in summer and 90% in winter. 332 plant species have been recorded for the dromedary, which include Artistida pungens, Acacia tortilis, Panicum turgidum, Launaea arborescens and Balanites aegyptiaca in the Sahara. Australian feral camels prefer Trichodesma zeylanicum and Euphorbia tannensis, while in India dromedaries are fed Vigna aconitifolia, V. mungo, Cyamopsis tetragonolaba, Melilotus parviflora, Eruca sativa, Brassica campestris and Trifolium species.^[11] Its highly preferred species include Santalum acuminatum, S. lanceolatum, Acacia sessiliceps, Pittosporum angustifolium, Erythrina vespertilio, and Lawrencia species.^[23] No matter which area it is in, the dromedary feeds on Acacia, Artiplex and Salsola plants.^[11]

They keep their mouth open while chewing thorny food. They use their lips to grasp the food, then chew each bite 40-50 times. Features like long eyelashes, eyebrows, lockable nostrils, caudal opening of the prepuce and a relatively small vulva avoid injuries, especially while feeding.^[37] A study on the diet of the dromedary, done in eastern Ethiopia, showed that the camels spent most time in the day grazing. The young camels generally grazed for more time than adults. The adults did not graze much and mainly rested or did other activities in the wet season. Overall, grazing was most in the dry season while other activities prevailed in the wet season. Observations of their foraging behavior showed that Opuntia plants were the most-eaten plants in the dry season as Acacia brevispica in the wet season.^[38]

Dromedary camels have several adaptations for their desert habitat. A double row of eyelashes and the unique ability of closing their nostrils enables the camels to prevent the sand and dust from entering, even in a sandstorm. Dromedaries can conserve water by fluctuating their body temperature throughout the day from 34–41.7 °C (93.2–107.1 °F), which saves water by avoiding perspiration at the rise of the external temperature. The kidneys are specialized so that not much water is excreted. Groups of camels also avoid excess heat from the environment by pressing against each other.^[27]

Dromedary camels can tolerate greater than 30% water loss, which is almost impossible for most of other mammals. In the Sahara, they can survive for as long as October to April or May without water. In temperatures of 30–40 °C (86–104 °F) they need water every 10 to 15 days, and only in the hottest temperatures do they take water every 4 to 7 days. They drink at the speed of 10–20 L (2.6–5.3 US gal) per minute.^[11] Water is expended primarily from interstitial and intracellular bodily fluids. They have the unique capability of drinking 100 L (26 US gal) of water in just 10 minutes.^[2] A very thirsty animal can drink up even 30 U.S. gal (110 L) of water in only 13 minutes^[39][11] and 200 L (53 US gal) in three minutes.^[40]

The hump stores up to 80 lb (36 kg) of fat, which a camel can break down into water and energy when sustenance is not available. If the hump is small, the animal can show starvation. In a study it was found that the mean volume of adipose tissues (in the external part of the hump), that have cells to store lipids (adipocytes), is related to the dromedary's unique mechanism of food and water storage.^[41] In case of starvation, they can even eat fish and bones, and drink brackish and salty water.^[17] The hair is longer at the throat, hump and shoulders. The pads widen under the weight of the dromedary when it steps on the ground.^[2][39] This prevents the dromedary from sinking much into the sand. When the dromedary walks, it moves both the feet on the same side of the body simultaneously, then the same movement is repeated on the other side of the body. This way of walking makes the body swing from side to side as the dromedary walks ahead, hence the nickname of the animal: "the ship of the desert".^[27] The thick lips help in eating coarse and thorny plants.

Females reach sexual maturity around 3 years of age and mate around age 4 or 5. Males begin to mate at around 3 years of age, too, but still are not sexually mature until six years of age. Breeding occurs in winters but is peak in the rainy season. The onset of the breeding season is believed to be cued by nutritional status of the camel and the daylength.

If mating does not occur, the follicle, which grow during estrus, usually regress within a few days.^[42] In a study 35 complete estrus cycles were observed in five non-pregnant females over a period of 15 months. The cycles were about 28 days long, in which follicles matured in six days, maintained their size for 13 days and returned to their original size in eight days.^[43] In another study it was found that ovulation could be best induced when the follicle reaches a size of 0.9–1.9 cm (0.35–0.75 in).^[44] In another study, pregnancy in females could be recognized as early as 40 to 45 days of gestation by the swelling of the left uterine horn, where 99.52% of pregnancies were located.^[45]

During the reproductive season, males splash their urine on their tails and nearer regions. Males also extrude their soft palate. Copious saliva turns to foam as the male gurgles, covering the mouth.^[2] Males threaten each other for dominance over the female by trying to stand taller than the other, making low noises and a series of head movements including lowering, lifting, and bending their necks backwards. A male tries to defeat other males by biting at his legs and taking the opponent's head in between his jaws.^[2] Copulation begins with a necking exercise. The male smells the female's genitals, and often bites her in this region or around her hump. The male makes the female sit, and then grasps her with his forelegs. Normally there are three to four ejaculations. The camelmen often aid the male to enter his penis into the female's vulva, though he is considered capable enough to do that himself.^[46] Copulation time ranges from 7–35 minutes, averaging 11–15 minutes.

A single calf is born after a gestational period of 15 months. Calves move freely by the end of their first day. Nursing and maternal care continues for one to two years.^[2] There was a study to find whether young could exist on milk substitutes. Two male young camels, one month old, were separated from their mothers and were fed on milk substitutes prepared commercially for lambs by the Mabarot Chemical and Veterinary Products (Israel). For the initial 30 days, the changes in their weights were marked. Each gained 0.400 kg (0.88 lb) and 1 kg (2.2 lb) respectively per day. Finally, they were found to have grown properly and weighing normal weights of 135 kg (298 lb) and 145 kg (320 lb).^[47]

The dromedary camel occupies arid regions, notably the Sahara desert in Africa. The original range of the camel’s wild ancestors was probably south Asia and the Arabian peninsula.^[27] They inhabit the dry hot regions of north Africa, Ethiopia, Near East and western to central Asia.^[48] All African camels are dromedaries, of which 84% occur in Somalia, Ethiopia, Sudan, Djibouti and Kenya,^[11] which constitutes 60.1% of the world's whole camel population.^[49] In the Horn of Africa, the dromedary can occur as far south as 2°S, where the annual rainfall may be 550 mm (22 in). The dromedary overlaps in distribution with the Bactrian camel in Afghanistan, Pakistan and southwest Asia.^[50] Richard Bulliet has observed that dromedaries exist where the Bactrian camel do not, and Bactrian camels exist where dromedaries do not occur. He concluded this can be because the nomads of Syrian and Arabian deserts valued the dromedary more, whereas Asiatic people raised the Bactrian camel.^[49]

Today they are commonly found in African, Arabian, Indian and Middle Eastern deserts. Extinct in the wild, today all dromedaries are domesticated. There are about 15 million domesticated dromedaries.^[27] The dromedary camel is also found in feral populations in northern Australia, where it was introduced in 1840.^[51][27] Populations survive in the Canary Islands, where they were exported in 1405. Attempts had been made to introduce dromedaries into the Caribbean, Colombia, Peru, Bolivia and Brazil; some were imported to the western United States in the 1850s and some to Namibia in the early 1900s, but today they exist in none of these areas.^[11] Short-term home ranges of feral camels in Australia are 50-150 square kilometers, and annual home ranges are estimated to be several thousand kilometers.^[11]

Dromedaries are used as beasts of burden in most of their domesticated range. Unlike horses, they kneel for the loading of passengers and cargo. It has been estimated that a camel can carry 159–295 kg (351–650 lb) for 24 km (15 mi) for a long time, but that may not be possible in the case of 544 kg (1,199 lb). Camels can be trained to bear loads from five years of age, but must not be given a large load until six years old. It has been found that camels are patient animals, easier to train and tougher than cattle. Camels can also be used to pull carts, plough and draw wheels. A dromedary can plough at a speed of 2.5 km (1.6 mi) per hour, but must not be worked for more than six hours a day. Their hair is durable and light, so it is used as a source material for woven goods, ranging from Bedouin tents to garments. The hair is clipped off using hand shears, or sometimes simply pulled, after which the camel's body is oiled. Juveniles less than two years of age have a fine undercoat, which is also used for these purposes. They also give wool. The wool produce of a herd of 4300 dromedaries in Russia in 1970 and 1974 were 557 kg (1,228 lb) and 576 kg (1,270 lb).^[52]

Camel milk is a staple food of desert nomad tribes. According to a study, it consists of 11.7% total solids, 3% protein, 3.6% fat, 0.8% ash, 4.4% lactose, 0.13% acidity (pH of 6.5). The quantities of sodium, potassium, zinc, iron, copper, manganese, niacin and vitamin C were relatively higher than the amounts in cow's milk. At the same time amounts of thiamin, riboflavin, folacin, Vitamin B₁₂, pantothenic acid, vitamin A, lysine and tryptophan were lower than the amounts in cow's milk. It was found that the molar percentages of the acids in milk fat were 26.7% for palmitic acid, 25.5% oleic acid, 11.4% myristic acid, and 11% palmitoleic acid.^[53] The camel milk has higher heat stability compared to cow's milk.^[54]

Daily yield generally varies from 3.5–35 kg (7.7–77.2 lb) and from 1.3 to 7.8% of the body weight.^[55] Amount of milk yield and milking frequency in dromedaries varies geographically, and depends upon their diet and living conditions. For example, Adal camels yield a maximum of 10.4 kg (23 lb) a day, while the Pakistani dromedary, considered a better milker and bigger, can yield 9.1–14.1 kg (20–31 lb). Dromedaries in Murrah (Arabia) can be milked once a day, while those in Afar (Ethiopia) may be milked six or seven times a day. A healthy female can give 9 kg (20 lb) of milk per day during the peak of lactation. Lactational yield can vary with species, breed and the general factors like region, diet, lactating stage.^[56]

The dromedary milk was studied to find its ability to form curd, in which catalysts were noted. The milk coagulation did not show actual curd formation, and had a pH of 4.4. It was much different from that of cow's milk, and had a fragile and heterogeneous structure perhaps composed of casein flakes.^[57] Still, today cheese, even hard cheese, and other dairy products can be made out of the camel's milk. J. P. Ramet of the FAO has also succeeded in making cheese in 1987. A special factory has been set up in Nouakchott to pasteurize and make cheese out of camel's milk.^[58]

The dromedary meat is a good source of food, composed of 78% water, 19% protein, 3% fat, and 1.2% ash and a small amount of intramuscular fat. The carcass is composed of 57% muscle, 26% bone and 17% fat. Seven to eight year old camels can produce a carcass of weight 125–400 kg (276–882 lb). The meat is a raspberry red to a dark brown or maroon, while the fat is white in color. It tastes like beef and has the same texture. Dromedaries can produce 500 g (1.1 lb) weight every day. Now-a-days camel meat is processed into food items like burgers, patties, sausages and shawarma.^[59]

In a study of the fatty acid composition of raw meat taken from the hind legs of seven young males (one to three years old), 51.5% were saturated fatty acids, 29.9% monosaturated and 18.6% polyunsaturated fatty acids, in chains. It was found that the major fatty acids in the meat were palmitic acid (26.0%), oleic acid (18.9%) and linoleic acid (12.1%). In the hump palmitic acid was dominant (34.4%), followed by oleic acid (28.2%), myristic acid (10.3%), stearic acid (10%).^[60]

A 2005 report, issued jointly by the Saudi Ministry of Health and the United States Centers for Disease Control and Prevention, details cases of human bubonic plague resulting from the ingestion of raw camel liver. Four of the total five patients had severe pharyngitis and submandibular lymphadenitis and had consumed raw camel liver. Yersinia pestis was isolated from the camel's bone marrow, as well as from the jird (Meriones libycus) and fleas (Xenopsylla cheopis) captured at the camel's corral.^[61]

• M. M. Sophie Smuts, A. J. Bezuidenhout (1987). Anatomy of the dromedary. Clarendon Press.

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• Information from ITIS
• The dictionary definition of dromedary at Wiktionary