The two-humped camel (Camelus bactrianus)

J. Lensch

The author is President of the Yak and Camel Foundation, PO Box 10, 25350 Krempe. His address is Stiftstr. 17, 25361 Krempe, Germany.

Note: This report was compiled after several visits to Inner and Outer Mongolia from 1993 to 1996. In 1987 and 1988, the author spent several weeks at the Dromedary Research Station in Bikaner, India.

LE CHAMEAU DE BACTRIANE (CAMELUS BACTRIANUS)

Cette étude présente le chameau de Bactriane (Camelus bactrianus),originaire d'Asie centrale, et ses cinq utilisations potentielles: lait, viande, laine, déjections comme sources d'énergie, et capacité de travail. En outre, elle met en évidence les différences qui existent entre le dromadaire (C. dromedarius), ou chameau des plaines, et le chameau proprement dit (C. bactrianus), ou chameau des montagnes, et décrit les animaux que l'on obtient par croisement. Il ne s'agit que d'une brève présentation ayant pour objet d'encourager la réalisation de travaux scientifiques ultérieurs sur le chameau de Bactriane, qui est une espèce menacée, puisque ses effectifs ne cessent de diminuer, et qui, tout comme le yack, permet à l'homme de survivre dans des conditions climatiques extrêmes.

EL CAMELLO (CAMELUS BACTRIANUS)

En este estudio se presenta el camello (Camelus bactrianus), nativo de Asia central, y sus cinco posibles aplicaciones: leche, carne, pelo, estiércol como fuente de energía y capacidad de trabajo. Además, se indican las diferencias entre el dromedario (Camelus dromedarius), o camello de las llanuras, y el camello de dos jorobas (Camelus bactrianus), o camello de las montañas, y se describe su descendencia híbrida. El estudio tiene por objeto presentar un panorama general. Se busca fomentar nuevas investigaciones científicas sobre el camello, especie en peligro debido a que su población disminuye constantemente y que, al igual que el yak, permite a las personas sobrevivir en condiciones climáticas extremas.

Camels are considered to be descended from the wild camel (Camelus ferus przewalski). The genus Camelus is thought to have migrated from America to Eurasia in the Pleistocene age. A distinction is made between the one-humped dromedary and Arabian camel (Camelus dromedarius), the camel of the plains, and the two-humped or bactrian camel (Camelus bactrianus), the camel of the mountains. (The word bactrianus comes from Bactria, a kingdom at the foot of the Hindu Kush Mountains of ancient Persia.) These large camels are also known as Old World camels, while the small humpless camels native to the Andes in South America are referred to as New World camels. There are several species of these small camels: the domesticated llama and alpaca and their wild forms, the vicuña and the guanaco. Unlike the large camels, they are remarkably proficient climbers. This ability was of inestimable value to the Incas, who used the llama on their transport route across the terraced mountains of the Andes.

The purpose of this study is to give an overview of the bactrian camel as a multipurpose livestock species. In view of the dramatic decline in the population of bactrian camels, particularly over the last few decades, the study also serves as an appeal to scientists to ensure the survival of this endangered species beyond the next millennium.The world population of small Old World camels is estimated to be 7 million.

The genus Camelus, like the genus Lama, belongs to the suborder Tylopodahich, which in turn belongs to the order Artiodactyla. A distinguishing feature of the tylopods, as the name suggests, is the structure of the foot. Tylopods walk on the tips of their hooves, and not on the soles of their feet like other ungulates. Unlike the llama, the camel has both toes fused together to form a common sole, and this prevents the animal from sinking in the desert sand. The horny pads are another distinguishing feature and are particularly pronounced in the two-humped camel. They are flat, leathery, localized pads on the volar carpal surface, elbows, knee region and sternal region, and they enable the camel to lie down on hard, uneven surfaces without injuring its skin or the underlying muscles. The pads also protect the camel from burning itself on the hot sand. Camels lack a stifle fold, which is a stretch of skin that connects the abdominal region with the thigh. The absence of the stifle fold is very important because the air can circulate under the abdomen from one side of the body to the other when the animal is lying down. Without the stifle fold, it is also much easier for the camels to walk, and they can use their limbs with great precision within a large radius.

While the dromedary (of which there are 17 million) inhabits Africa, southwest Asia and south Asia, more than 90 percent of the habitat of the bactrian camel lies in Inner Mongolia (China), Outer Mongolia (Gobi Desert) and the desert steppes of Kazakhstan.

The dromedary is known as the camel of the plains because it has great difficulty in travelling through mountainous regions. The two-humped mountain camel mainly inhabits the mountains of central Asia at altitudes of up to 2 000 m. In exceptional circumstances it can also cross passes at higher altitudes, even when they are covered in snow. Cave paintings suggest that the bactrian camel was domesticated in Mongolia during the Neolithic age (3000 to 1800 bc).

Today, the wild form of the bactrian camel (about 10 000 animals) is found exclusively in the Gobi Desert. Feral dromedaries are found only in Australia, where camels imported from Africa were released into the wild last century after the introduction of the motor car.

Unlike the dromedary, which generates a great deal of scientific interest, the bactrian camel has so far been largely neglected by scientists in the western world. Given the extreme climate and inordinate language problems (Chinese, Mongolian and Russian), only very few western scientists have been willing to conduct their research on the spot. In order to rectify this situation, the Yak and Camel Foundation, which was set up in Germany several years ago, has taken up intensive research activities in Mongolia on the subject of camels. The aim of this research is to study the behaviour, nutrition and health of the mountain camel and, ultimately, to compile scientific documentation on this topic.

GENERAL INFORMATION

In the desert steppes of central Asia, where camels are kept as livestock, the annual precipitation is 80 to 120 mm (this includes snow in the winter months). The animals also have a basic food supply in the winter because the snow cover is relatively thin. The climate is extremely continental, consisting of hot summers with temperatures up to 55°C

(2 000 to 2 500 hours of sunshine per year) and cold winters with temperatures as low as -40°C. Desert steppes are tree

less grass plains where the vegetation primarily consists of more or less long grasses, depending on the humidity, bulbous plants and perennials. During prolonged drought, the steppes can develop into thorn bush plains. The vegetation in the steppes predominantly comprises common saltwort and shrubs that can be utilized optimally only by camels. It is thanks to their anatomy that they are able to feed on thorny plants rich in raw fibre. Their split upper lip and long tongue, which is lined with a thick pavement epithelium, enables them to pluck leaves from thorn bushes without incurring injury.

The camel, particularly the bactrian camel, needs to ingest large quantities of salt. This dietary requirement may have developed during the course of the animal's adaptation to the desert steppes, where brackish water and halo-phytes with a high salt content can often be found. We know from Mongolian sources that camels are particularly fond of salt lakes and grazing land with a high salt content where they can ingest as much salt as they like. The bactrian camel's daily salt requirement, obtained from saline plants and brackish water, is estimated to be between 60 and 120 g. A golden rule, according to Mongolians, is that camels must be given an extra supply of salt on long journeys. The white efflorescence, called "gudschir", which is found on the ground of the desert steppes, plays a major role in the mineral balance of the camels. When they have access to saline plants, camels refuse all other food. They become emaciated if their diet lacks salt, even if there is a large supply of salt-free food available. The animals look weak, their two fatty humps shrink to one-third of their original size and they can no longer transport heavy loads over long distances.

PASTURE

It can be assumed that an adult bactrian camel requires a feeding area of 80 to 100 ha in the steppes. The Gobi Desert, which extends over 500 000 km², is home to between 400 000 and 500 000 camels. Several years of observation have revealed that bactrian camels have remarkably extensive grazing habits. They never consume entire plants, and they cover a distance of 10 to 15 km during their daily intake of food. The total dry mass consumed by camels every day is estimated to be from 6 to 12 kg in the summer months and from 4 to 6 kg in the winter months. Their preferred feeding times are in the morning and evening, and between these times the animals ruminate for several hours. The camel herds are looked after by nomadic herdsmen, although women are responsible for milking. Nomadic herders are animal owners whose lives are geared exclusively towards livestock rather than arable farming. They live on vast steppes covered in grass and thorn bushes and their nomadic way of life is adapted to the animals. The economic unit is the extended family (four to six children, parents and grandparents) in which women play a pivotal role. Children as young as six years milk goats and, in the summer months, girls aged from 14 to 18 take charge of 60 to 80 camels each, astride their Mongolian steppe horses.

BIOLOGICAL CHARACTERISTICS

In order to obtain an accurate picture of camels as inhabitants of the desert steppes, the reader must consider certain biological characteristics. Unlike cattle, which lose 7 to 8 percent of their body weight per day if they have no access to water, the bactrian camel loses only 1 to 2 percent, which means that it can survive for two to three weeks without water in exceptional circumstances. It can also take in more than 100 litres of liquid (150 litres in the case of lactating camels) within a few hours. It can be assumed that other large mammals would die if they lost 25 to 30 percent of their body weight through dehydration, which means that cattle can go without liquid for three to four days at the most. In autumn and winter, the camel can meet part of its water requirement through snow intake. The daily body temperature of the bactrian camel fluctuates from 34°C in the early hours of the morning up to 40°C in the evening. The rise in body temperature indicates that body heat is stored during the day and released during the cool nights without major water loss. The camel also has a covering of wool, which acts as an insulating layer and fulfils the complex task of regulating body heat. To sum up, the unusual water balance in the camel is characterized by a low level of evaporation and greatly delayed dehydration. Moreover, the camel can consume dry food for long periods of time without taking in water.

The two humps of the bactrian camel are about 25 to 35 cm high. Their function is not, as is often mistakenly assumed, to store water but to store energy. Unlike the elastic hump of the dromedary, the two humps of the bactrian camel are largely inflexible, so that they flop over to one side once all the fat reserves have been depleted. The breakdown of fat always starts in the caudal hump. Each fatty hump contains around 25 to 35 kg of fat, which is equivalent to a calorie reserve of 250 000 to 350 000 kcal. The appearance of the two humps (firm and full or flaccid) is an indicator of the nutritional state of the camel. The humps contain most of the body fat. The subcutaneous connective tissue is largely fat-free, which facilitates the release of redundant body heat.

The bactrian camel herd studied in Outer Mongolia
Troupeau de chameaux étudiés en Mongolie extérieure
El hato de camellos bactrianos estudiado en Mongolia Exterior

REPRODUCTION

Some reproductive characteristics of the bactrian camel must be pointed out if the reader is to understand the behaviour of this animal, as there are several fundamental differences between reproduction in the camel and reproduction in cattle. The bactrian camel reaches sexual maturity at the early age of two to three years, although mating usually takes place at a later stage (at four to five years of age). According to information from Mongolia, the cow remains fertile for up to 25 years. Oestrus occurs on a seasonal basis from January to May, and the oestrus cycle lasts 16 to 20 days. There are only clearly visible signs of oestrus from two to four times during the entire mating season. Ovulation is induced by copulation and occurs 20 to 30 hours after mating. The nomads usually use one bull for every 40 to 60 cows.

Male bactrian camels, whose temperament can generally be described as indifferent, become unpredictable and aggressive towards humans during the rutting season. The camel's upper incisor and its canines (two diastemas), which are particularly pronounced in the bactrian camel, are exposed, so that the large hooked teeth act as dangerous weapons. The distended soft palate, which is the size of a tennis ball, protrudes from the animal's mouth. It grinds its teeth and large quantities of foam can be seen in the oral cleft. A considerable loss of appetite is observed, and sometimes the animals stop feeding altogether. A dark, foul-smelling substance is secreted from between the ears. The hind legs are splayed so that the tail can strike the penis. The animals also urinate more frequently, and the urine is sprinkled across the body by movements of the tail, which gives rise to a smell of urine. When it comes to copulation, the female lies on her stomach so that the male always serves in a sitting position. Copulation lasts from several minutes to half an hour, and in exceptional cases up to three ejaculations have been observed. It is not unusual for a bull to serve the same cow several times on a given day if there are no other available cows in oestrus.

The rate of conception is between 45 and 55 percent (twin births are thought to make up less than 1 percent). Pregnancy can be detected from the 45th to the 50th day by rectal examination, and is visible externally six to seven months after copulation. The gestation period is between 13 and 14 months, and the involution of the uterus is completed 45 to 50 days after delivery. The mother sniffs the newborn calf but does not lick it. In the first week of the calf's life, maternal care is particularly intensive because the animal must learn how to walk and suck. Newborn two-humped camels weigh between 35 and 45 kg. Their bodies are covered with long, thin wool hair that acts as protective blanket on the surface of the body.

SALIENT FEATURES

Bactrian camels have five potential uses, a fact that distinguishes them from cattle with regard to productivity:

· milk production;
· meat production;
· wool production;
· working capacity as a riding and pack animal;
· source of fuel from dried dung.

Milk production

The milk yield of the bactrian camel is lower than that of the dromedary and amounts to between l 000 and 1 500 litres per year. The maximum yield is reached in the third month of lactation. The dromedary has a much higher milk yield of 1 500 to 2 500 litres per lactation. The total milk yield can only be estimated because the calf consumes a substantial part of the milk. Camel owners estimate that 800 to 1 000 litres are consumed by the calf. The milk is rich in fat (5 to

7 percent). The milk of bactrian camels generally has a higher fat content than that of dromedaries, which means that it also has a higher caloric content. It contains 5 percent lactose and 4 to 5 percent protein, of which the lion's share (75 to 80 percent) is casein. It should be pointed out, however, that the components of camel milk do not remain constant; they depend on the season and the vegetation. The author was able to see for himself that the shelf-life of camel milk differs greatly from that of cow milk. At a summer temperature of 40°C, camel milk retains its typical odour for up to 12 hours. During this time the milk does not turn sour, whereas cow milk turns sour after only two to three hours. At temperatures below 10°C, camel milk can be stored for up to 60 hours without souring and, therefore, without loss of quality.

The milk is fermented to make a sour-tasting drink called "schubat". The method for making this drink is similar to the process used to make "kumys" from cow milk. In addition to "schubat", camel milk is used to make butter, cheese, curd and yoghurt. "Schubat" is also administered to both humans and animals to treat diseases of the respiratory or digestive systems. The same applies to rachitic diseases in young children. There are no major problems with mastitis. The diseased quarter is treated purely by frequent milking so that no drugs are required. According to Russian data, 10 to 15 percent of camels in Kazakhstan are chronically infected with Brucella abortus. The author is not aware of any studies on Brucella abortus in Mongolia or China.

Meat production

Bactrian camel meat has coarser fibres than beef but is comparable with lean beef in terms of quality. Camel meat has a high biological value. The colour of the meat is raspberry red to dark brown, and it has a sweet taste because of the high glycogen content. The meat of older animals is nearly always tough and has a characteristic odour which is not eliminated by cooking. The fat is white in colour.

Camel meat production is described below using the example of Kazakhstan. While dromedary farmers in East Africa often specialize in milk and meat production, there is relatively little meat production in Kazakhstan. The slaughter yield of bactrian camels is between 50 and 60 percent, and the fat content is estimated at 8 to 18 percent. The energy content per kg meat is 1 200 to 1 200 kcal. The slaughter animals are divided into three groups: adult camels (more than three years old); juvenile camels (one to two years old); and calves (less than one year old).

In terms of consistency, bactrian camel meat is similar to beef. It is eaten both fresh and dried. In Kazakhstan, camels are slaughtered in October and November, the timing being largely determined by the declining availability of grazing land. Following the winter months, the slaughter animals are grouped together according to age and sex and taken to grazing land in the steppes. This land provides the best feeding basis for the animals. They stay there until October or November. According to camel owners, the daily weight gain during the grazing season is 800 to 900 g in juveniles and 600 to 650 g in adult animals. By the end of this "fattening" period, a large mass of fat has accumulated in the two humps, each of which weighs 25 to 35 kg. Unlike North and East Africa, the Arabian Gulf states and Saudi Arabia, where there is a strong buyer's market for camel meat of any quality, the demand in Kazakhstan, Mongolia and China is of minor importance, which is naturally reflected in the pricing.

Animals under study in the compound
Animaux à l'étude dans un enclos
Los animales objeto de estudio en su recinto

Wool production

Unlike dromedaries, bactrian camels have a long, prolific winter fleece, extending as far as the mane and the lower part of the neck. There is an extensive tuft of hair on the frontal side. The forelimbs, starting from the elbow joints towards the head, are covered with long strands of hair. The colour of the fleece varies from russet to dark brown or, in exceptional cases, light grey. In spring (April and May) the coat moults in clumps that hang from the animal's head, neck, back and legs. These clumps are continually knocked off or removed by hand. The coat consists of down, wool and hair. The length and width of the hair fibres vary, depending on the part of the body concerned. Around the ribs and shoulders, the wool is particularly fine and dense. The annual wool yield of a male camel is 12 to 15 kg and that of a female 6 to 8 kg. Hair accounts for about 44 percent of the coat, while down and wool account for about 56 percent. The camels are usually shorn once a year (in spring) and the wool is processed in factories. The proportion of usable wool ranges from 80 to 90 percent, since the wool contains only a few foreign bodies and some dust. All woollen products made from camel wool are of an extremely high quality. Although camels make up only 2 percent of livestock in Mongolia, they are responsible for 10 percent of agricultural products and 17 percent of the total wool production.

Working capacity

In the desert steppes of central Asia the camel still plays an important role as a beast of burden and as a riding animal, although it has lost its dominant status since the Second World War. The camel is remarkably well adapted to the extreme climate of the desert, where temperatures can fluctuate by as much as 90°C during the course of the year. Camels are used for transporting loads primarily in the autumn and winter and to a limited extent in the wet summer months (90 percent of the precipitation falls in the three summer months) because of the high humidity. As soon as autumn approaches, the nomads round up their camels and prepare them for winter trips. In autumn and winter the camels can withstand temperatures as low as -40°C and a high level of travel-induced strain, since the humidity during these seasons is usually lower than 30 percent. Snowfall in winter generally results only in a thin cover and settles for no more than a few days. For Mongolian camel owners it is an unwritten law that in summer the camels must be allowed to graze freely in the steppes to preserve their strength as far as possible and to ensure that they are optimally prepared for their function as pack animals during the winter. The bactrian camel can withstand the extreme heat as well as the extreme cold because it has adapted to the desert steppes of central Asia.

The examples below illustrate the economic and military importance of the two-humped mountain camel. Marco Polo's travel reports infer that, for hundreds of years, silks were transported along the famous Silk Road from China to Europe exclusively by camel. Another point worth mentioning is that Genghis Khan and his commanders used mobile camel residences (command centres). These dwellings could be built up and taken down in a day, and a total of 500 to 1 000 camels were used to transport each dwelling. Apparently more than 1 million military camels were constantly used during the Mongolian campaigns to carry the necessary supplies of clothes, provisions and war material for the cavalries in the Mongolian empire, which stretched from the China Sea to Europe - very impressive logistics, even by today's standards. The only drawback to the camel transport system was that no large campaigns could be carried out in the summer rainy season. Mongolian camels have also played a major role in the twentieth century, and they may even have had a decisive impact on the Japanese-led war between the empire of Manchukuo and the Mongolian People's Republic. In autumn 1939, this war was won by the Mongolians and their Russian allies because they had large numbers of pack camels, while the Japanese used motor vehicles and were thus reliant on difficult fuel supplies. (The Russian waiver of reparations led to the pact of non-aggression between the Russians and the Japanese, which in turn was of considerable importance to the outcome of the Second World War.)

Camels are also used to transport yurts (circular tents), called "yurt" in Russian and "ger" in Mongolian, of which there are still hundreds in the Gobi Desert. Yurts have a circular sliding lattice grate made of wooden poles with flat, rod-shaped bars placed on top to form the roof. The roof bars are covered with felt blankets and are always lined with carpets or, in exceptional cases, grass mats. The smoke from the fire set up in the middle of the tent is released through a smoke outlet in the roof. Yurts are usually from 2 to 3 m high and about 8 m in diameter. They can be dismantled within a few hours and transported to another site on the backs of two or three camels. Yurts provide optimum protection from the heat in summer and the cold in winter.

Working animals are primarily bulls or castrated males of at least four years old. Their working capacity reaches its peak at the age of seven to eight years. The camels designated for work purposes receive intensive training at the age of three to four, and are fitted with a wooden nose ring. Male pack camels are usually castrated at the age of two to three. According to verbal records, working camels can be used for 15 to 20 years. As a rule, adult camels can carry a load of about 40 percent of their body weight, which is double the potential of the juvenile animals. Since the average weight of a male camel is about 600 kg and that of a female is about 400 to 500 kg, the load capacity amounts to 200 to 240 kg and 150 to 200 kg, respectively. During the summer months camels travel from 4 to 6 km per hour, while in the winter months they can cover 8 to 10 km per hour. On journeys lasting for several weeks, camels cover a distance of approximately 30 to 40 km per day. On shorter journeys, lasting less than a week, they cover 80 to 100 km per day. In exceptional circumstances, bulls are able to walk more than 120 km in a single day, provided that they have a whole day to rest afterwards.

Camel dung as a source of energy

Dried camel dung, of which the dry matter content is twice that of dried cattle dung, is one of the few sources of energy available to camel owners in the desert steppes of central Asia. Every year about 950 kg of dung are collected per adult animal. The compact balls of dung have a high caloric value and are highly rated as fuel. Since the dung burns with a low, long-lasting and virtually smoke-free flame, the women can start cooking well in advance of mealtimes and can leave the tent now and again while the food is being slowly heated. Since the burning process produces little smoke, the yurt dwellers are not exposed to smoke pollution.

CROSS-BREEDING

In modern camel research, the one-humped and two-humped camels are assumed to have the same origins, and crosses between the two species are termed hybrids. The parents have the same number of chromosomes - which is also the case for the swamp (45) and riverine (50) buffaloes. According to camel owners, there is a heterosis effect insofar as the working capacity, milk and meat yields of cross-bred camels are improved by 30 to 40 percent. The disadvantages of the F₁ generation are increased susceptibility to disease, higher feeding requirements and lower fat reserves owing to the vestigial front hump. Both the male hybrids, also known as "nar", and the female hybrids, or "nar maia", are fertile. Backcrosses of the hybrids with the one-humped and two-humped camels were abandoned because they yielded no economic advantage.

It is clear from the above information that the desert steppes of central Asia, which stretch over 1.5 to 2 million km², could not be used by humans if it were not for the bactrian camel. Consequently, there is an urgent need for fundamental studies on the behaviour, nutrition and health of this endangered species, with a special emphasis on parasitological problems. Happily, the opening up of the central Asian states and China from a political point of view has now created favourable conditions for scientists to carry out research studies on the spot.