Camelus bactrianusBactrian camel

Ge­o­graphic Range

Camelus bac­tri­anus, also known as the Bac­trian camel, in­hab­its parts of cen­tral Asia and west­ern China. The ge­o­graphic range is now lim­ited to iso­lated re­gions of the Gobi and Tak­la­makan Deserts of Mon­go­lia and Xin­jiang. The Bac­trian camel's ge­o­graphic range has been steadily de­creas­ing for the last 30 years. (Chen, et al., 2009; Cui, et al., 2007; Makhdoomi, et al., 2013; Men­goli, et al., 2005; Nowak, 1999)

Habi­tat

  • Average elevation
    1,580 m
    ft

Phys­i­cal De­scrip­tion

The dis­tin­guish­ing char­ac­ter­is­tic that sets Bac­trian camels apart from drom­e­dary camels (Camelus drom­e­dar­ius) is that they have two humps on their backs (drom­e­dary camels have just one). Bac­trian camels are large an­i­mals with an av­er­age height of 2.134 m. The length of the head and body is 2.25-3.45 m, the tail is 0.35-0.55 m long, and the shoul­der height is 1.80-2.30 m tall. The weight of the adult camel can range from 300-690 kg. Adult male Bac­trian camels are often much larger than the adult fe­males; how­ever the exact mea­sure­ments have not been ac­knowl­edged in schol­arly re­search.

Camel coat color is typ­i­cally dark brown or a dirty gray color. Ex­clu­sive to the Bac­trian camel is their long hair (255mm long). The coat is thicker and heav­ier on the head, neck, humps, forelegs, and tail re­gions. The dras­tic sea­sonal tem­per­a­ture changes in the desert re­quire Bac­trian camels to shed their heavy coat when the sea­sons change.

De­spite en­dur­ing high am­bi­ent tem­per­a­tures, Bac­trian camels have min­i­mal sweat glands. In­stead, they have the abil­ity to tol­er­ate an in­ter­nal tem­per­a­ture in­crease of 6 de­grees Cel­sius be­fore per­spir­ing, which pre­vents water loss.

Bac­trian camels have a dou­ble row of long eye­lashes that block harsh winds that often blow sand and dust into the camels' eyes. Their ears are also lined with hair and their top lip is di­vided. The nos­trils can close to shield against dust and sand. There is a con­nect­ing in­dent that runs along each nos­tril to the cleft top lip so that any extra water or mois­ture can be trapped in the mouth. The camels' even toed feet are tough and the soles are un­di­vided. (Chen, et al., 2009; Makhdoomi, et al., 2013; Nowak, 1999)

  • Sexual Dimorphism
  • male larger
  • Range mass
    300 to 690 kg
    660.79 to 1519.82 lb
  • Range length
    2.25 to 3.45 m
    7.38 to 11.32 ft

Re­pro­duc­tion

Both camel species are polyg­y­nous, where the dom­i­nant male will mate with any of the fe­males in the herd. The rut­ting sea­sons lasts about three months. The dom­i­nant male will often pro­tect and de­fend the fe­males within the group from other wan­der­ing bach­e­lor camels. How­ever, no pub­lished ar­ti­cles iden­tify how the alpha male is de­ter­mined within the group. Through­out the mat­ing sea­son males tend to fight, bite, spit, and snort to in­tim­i­date and scare away in­trud­ing males. (Elias and Cohen, 1986; Mostafa, 2010; Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008)

The Bac­trian camel's breed­ing sea­son takes place in March and April. Camels are in­duced ovu­la­tors, which means they only ovu­late when stim­u­lated by mat­ing. If a fe­male does not have the op­por­tu­nity to mate, her ovar­ian fol­li­cles will de­gen­er­ate. Their es­trous cycle is about 13-40 days, and re­cep­tiv­ity usu­ally last be­tween three and four days. Ges­ta­tion is 360-440 days, re­sult­ing in one or two off­spring. Camels can birth up to two off­spring every two years, but more than one is rare.

Fol­low­ing this bi­en­nial cycle, each fe­male pro­duces an es­ti­mated 12 off­spring in her life­time. Calves are born weigh­ing about 37 kg and are fully mo­bile within the first 24 hours. Calves in the wild are typ­i­cally weaned within the first two years, but this can hap­pen within one year in cap­tiv­ity. The calf reaches full ma­tu­rity at age five, some­times six to eight years for males. It is more com­mon for males to reach sex­ual ma­tu­rity be­fore the age of five. Calves live close to their moth­ers for three to five years, and com­pletely sep­a­rate once sex­u­ally ma­ture. (Elias and Cohen, 1986; Mostafa, 2010; Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008)

  • Breeding interval
    Camels reproduce once every two years.
  • Breeding season
    Breeding season takes place between March and April
  • Range number of offspring
    1 to 2
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Range gestation period
    360 to 440 days
  • Range weaning age
    12 to 24 months
  • Range time to independence
    3 to 6 years
  • Average time to independence
    5 years
  • Range age at sexual or reproductive maturity (female)
    3 to 5 years
  • Average age at sexual or reproductive maturity (female)
    5 years
  • Range age at sexual or reproductive maturity (male)
    3 to 8 years
  • Average age at sexual or reproductive maturity (male)
    5 years

The fe­male camel is par­tic­u­larly in­vested in her parental du­ties, and re­mains so until the calf reaches full sex­ual ma­tu­rity. Within the first two years the mother weans the calf, but both mother and baby re­main very close to each other. In most cases the young camels stay with their mother until age five, when they reach sex­ual ma­tu­rity. Calves learn how to in­ter­act prop­erly with the other mem­bers of the herd as well as food for­ag­ing skills and mi­gra­tory pat­terns. Fe­male camels are pro­tec­tive of their young, and be­come vi­o­lent if threat­ened. Be­cause of this at­tach­ment, mother camels have been doc­u­mented mourn­ing the loss of a calf for as long as three months. (Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008)

  • Parental Investment
  • precocial
  • female parental care
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • female
  • extended period of juvenile learning

Lifes­pan/Longevity

Bac­trian camels have been known to live for as long as 50 years in the wild. How­ever, do­mes­ti­cated camels have never been recorded to live for more than 35.4 years. The av­er­age life ex­pectancy for wild Bac­trian camels is 30 years. There is lim­ited schol­arly lit­er­a­ture on any in­ter­nal or ex­ter­nal com­pli­ca­tions that may con­tribute to some of the ap­par­ent lifes­pan lim­i­ta­tions. ("Camelus bac­tri­anus", 2012; Nowak, 1999; Palmer, 1957; Smith and Xie, 2008)

  • Range lifespan
    Status: wild
    50 (high) years
  • Range lifespan
    Status: captivity
    35.4 (high) years
  • Average lifespan
    Status: wild
    30 years
  • Typical lifespan
    Status: captivity
    35.4 (high) years

Be­hav­ior

Wild Bac­trian camels typ­i­cally live in herds of 6-20 mem­bers, al­though they can oc­ca­sion­ally be soli­tary or in groups up to 30 in­di­vid­u­als. In their na­tive range, a pop­u­la­tion den­sity of five camels per 100 square km has been es­ti­mated. Camels are not ter­ri­to­r­ial an­i­mals. oc­ca­sion­ally mul­ti­ple camel herds will cross paths and form an as­sem­bly of camels, which can reach 500 in­di­vid­u­als. Camel herds spend the ma­jor­ity of their days mov­ing from one place to an­other graz­ing. Dur­ing the snowy win­ter months Bac­trian camels mi­grate to the Gobi desert steppe, a broad eco­tone that bor­ders many rivers. When the snow melts in the spring, Bac­trian camels mi­grate back to the desert.

The herds con­sist of one alpha adult male lead­ing adult fe­males and their calves. Once young males reach sex­ual ma­tu­rity, the alpha male chases them away, forc­ing the young males to join a group of bach­e­lor males. If a fe­male in the group is ap­proached by a wan­der­ing bach­e­lor male, the in­trud­ing male will be chased away by the dom­i­nant male. When the dom­i­nant male and a bach­e­lor male come in con­tact, they both dis­play an ef­fort to in­tim­i­date their op­po­nent. These dis­plays in­clude: uri­na­tion, defe­ca­tion, slap­ping their tail against their backs, and spread­ing their hind legs. If none of these dis­plays deter the com­peti­tor, the males re­sort to fight­ing, in­cludes bit­ing and beat­ing the ground with their feet.

Males tend to not eat dur­ing the rut­ting sea­son, and use their en­ergy re­serves to sus­tain them dur­ing this pe­riod. Schol­arly re­search hasn't de­ter­mined why males have adopted this coun­ter­in­tu­itive be­hav­ior. (Elias and Cohen, 1986; Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008)

  • Range territory size
    50 to 150 km^2

Home Range

Bac­trian camels are so­cial an­i­mals. These an­i­mals aren't ter­ri­to­r­ial, and herds often cross paths to form a large as­sem­bly. How­ever, the alpha male of each herd will con­tinue to de­fend and pro­tect the fe­males in the herd from bach­e­lor males. It has been ob­served that camels have tem­po­rary home ranges of 50-150 square km and yearly ranges of sev­eral thou­sand square km. (Elias and Cohen, 1986; Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008; Elias and Cohen, 1986; Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008)

Com­mu­ni­ca­tion and Per­cep­tion

Bac­trian camels have a well-de­vel­oped sense of sight, which is one of the pri­mary ways that camels per­ceive their sur­round­ings. There have been nu­mer­ous anatom­i­cal stud­ies that have shown that mem­bers of the genus Camelus have ex­cep­tional eye­sight that arose from the unique or­ga­ni­za­tion of their reti­nas. Camels also have well-de­vel­oped ol­fac­tory senses that are ex­tra­or­di­nar­ily strong and sen­si­tive. Camel nos­trils are ex­tremely sen­si­tive and can de­tect odors over long dis­tances, up to 3 km away.

Re­search on sim­i­lar un­gu­lates in­di­cates that these an­i­mals use pheromones to com­mu­ni­cate and send sig­nals. It is thought that camels also use the same or sim­i­lar pheromones. Vocal com­mu­ni­ca­tion has been re­ported in camels, such as deep moans, high pitch squeaks, and groans. Zoos re­port that camels are very vocal, al­though there is no schol­arly re­search re­gard­ing this. ("Camel", 2013; Har­man, et al., 2001; Nowak, 1999; Over, et al., 1990)

Food Habits

Bac­trian camels are om­ni­vores, but are pri­mar­ily her­bi­vores that con­stantly graze on grasses. As ru­mi­nants, these camels have four sep­a­rate stom­achs, one of which is a three-cham­bered ru­mi­nat­ing stom­ach. Ru­mi­nants eat their food fol­lowed by re­gur­gi­ta­tion, al­low­ing them to chew it up a sec­ond time.

Camels thrive on all desert veg­e­ta­tion, which in­cludes salty, dry, thorny, and bit­ter plants. Halo­phytic plants, which are plants that have been grow­ing in water with a high saline con­cen­tra­tion, are a nec­es­sary part of Bac­trian camel's diet. Their di­etary needs and pref­er­ences make them ideal can­di­dates for desert life.

In times of en­vi­ron­men­tal stress (lit­tle/no avail­able veg­e­ta­tion), camels may eat fish, dif­fer­ent types of flesh, bones, skin, and even shoes or other items of fab­ric. In the win­ter months, camels often push and dig under the snow to find food, a prac­tice ob­served only in Bac­trian camels.

The humps on the back of the camel are com­monly thought to store water, but in ac­tu­al­ity the humps store fat. The hump is made up of fatty tis­sues, which are used to store en­ergy for times when nu­tri­ents aren't read­ily avail­able. The en­ergy re­serves in the camels hump can be used in place of both water and food. Camels that are well nour­ished have humps that stand up­right and ap­pear plump and firm. Mal­nour­ished camels that are de­prived of vital nu­tri­ents have smaller and side­ways lean­ing humps. A camel with a nour­ished hump can live up to a cou­ple of weeks with­out eat­ing or drink­ing.

Along with the en­ergy re­serves that re­side in the fatty tis­sues of the camel's hump, the stom­ach is en­closed by cham­bers filled with water. They can also drink saline water, which in turn causes them to uri­nate con­cen­trated salt. The camels' kid­neys ef­fi­ciently elim­i­nate the un­wanted sur­plus of salt be­fore re­turn­ing the water back to the blood­stream. Camels can al­most be fully sus­tained from the water in the veg­e­ta­tion that they con­sume. They can with­stand a large amount of water loss, up to 40 per­cent of their body weight. Camels can con­sume up to 57 liters of water to fully re­store their body fluid lev­els. When camels come across an abun­dant water source, they will drink large amounts of water within a mat­ter of min­utes, to re­fill their water stor­age. This water stor­age will be­come use­ful dur­ing times of drought. (Er­dun­chaolu, et al., 2001; Men­goli, et al., 2005; Nowak, 1999; Wang, 2002; Er­dun­chaolu, et al., 2001; Men­goli, et al., 2005; Nowak, 1999; Palmer, 1957; Smith and Xie, 2008; Wang, 2002)

  • Animal Foods
  • birds
  • mammals
  • reptiles
  • Plant Foods
  • leaves
  • wood, bark, or stems
  • seeds, grains, and nuts
  • flowers

Pre­da­tion

Camelus bac­tri­anus has evolved in a par­tic­u­larly harsh en­vi­ron­ment that is unfit for the ma­jor­ity of preda­tors. How­ever, leop­ards (Pan­thera par­dus) and wolves (Canis lupus) are some­times found roam­ing around the colder re­gions of Asia. Camels aren't the leop­ards and wolves' pri­mary tar­get be­cause of the camels' enor­mous size and dif­fi­culty in killing. These preda­tors mainly ig­nore camels un­less they are starv­ing. Hu­mans (Homo sapi­ens) are the camels' biggest threat, as they are har­vested for meat, hides, wool, sinews, and bone. (Nowak, 1999)

Ecosys­tem Roles

Camelus bac­tri­anus nat­u­rally ac­quires cryp­tosporidio­sis and gas­troin­testi­nal helminthic par­a­sites. A wide range of helminth par­a­sites have been found in the gas­troin­testi­nal tract of Bac­trian camels. A study was con­ducted in Iran that ex­am­ined the oc­cur­rence of these gas­troin­testi­nal helminths. This study in­cluded a sam­ple size of 25 fecal sam­ples, which was 25% of the camel pop­u­la­tion. Helminth eggs were pre­sent in 52% of the fecal sam­ples. Bac­trian camels in this study were found to be con­t­a­m­i­nated with Ne­ma­todirus (32%), Trichuris (32%), Mar­shal­la­gia (28%), Moniezia (28%), and Strongy­loides (16%). The pro­to­zoan Cryp­tosporid­ium parvum is an­other com­mon par­a­site found in Bac­trian camels. This par­a­site shows dis­tinct signs in­clud­ing chronic loose stools, re­duced ap­petite, weight loss, and lethargy. The pres­ence of these par­a­sites has sig­nif­i­cant con­se­quences that can often re­duce the in­di­vid­ual's lifes­pan. (Fayer, et al., 1991; Tajik, et al., 2011)

Com­men­sal/Par­a­sitic Species

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Camelus bac­tri­anus is ex­tremely use­ful to hu­mans. Camels are com­monly used for trans­porta­tion through­out desert re­gions. The anatom­i­cal for­ma­tion of their feet aids in their abil­ity to go long dis­tances in harsh desert con­di­tions. Their abil­ity to go ex­tended pe­ri­ods of time with­out food or water also makes them ideal trans­porta­tion on long jour­neys in the desert. Hu­mans have been re­ly­ing on camels for 3,500 years for trans­porta­tion and other mar­ketable rea­sons. Camels pro­vide many use­ful byprod­ucts in­clud­ing meat, milk, hides, sinews, and bone. The milk is typ­i­cally fer­mented to pro­duce kumis,a drink typ­i­cally en­joyed by the na­tive peo­ple of the Cen­tral Asian steppes. The fat in the humps can be melted down and used for cook­ing pur­poses. Camel hair is often used to make clothes, blan­kets, tents, and other fab­ric con­tain­ing items. camel dung is fre­quently used to man­u­fac­ture fuel. Their hides are in­cor­po­rated into leather prod­ucts. Given this mul­ti­tude of uses, its no sur­prise that camels are fre­quently bought, sold, and traded within their range. (Ahmad, et al., 2010; Mostafa, 2010; Palmer, 1957; Skid­more, 2011; Wang, et al., 2013)

  • Positive Impacts
  • food
  • body parts are source of valuable material

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

For the most part camels have very few ad­verse ef­fects. Oc­ca­sion­ally, camels can be­come hos­tile. An ag­gra­vated out-of-con­trol camel can in­jure a human being be­cause of their enor­mous size, but this is very un­likely. A hun­gry camel can be­come a nui­sance by eat­ing per­sonal pos­ses­sions and by spit­ting. (Nowak, 1999; Palmer, 1957; Skid­more, 2011; Smith and Xie, 2008; Wang, et al., 2013)

  • Negative Impacts
  • injures humans

Con­ser­va­tion Sta­tus

Wild Bac­trian camels are cur­rently a crit­i­cally en­dan­gered species. It has been de­ter­mined that there are no­tice­able ge­netic dif­fer­ences (3%) be­tween the wild and do­mes­tic groups. The do­mes­ti­cated ver­sion isn't in­cluded in the en­dan­gered group, as their pop­u­la­tion ap­pears to be thriv­ing.

Wild Bac­trian camels are pre­dicted to de­crease in pop­u­la­tion size by >80% within the next three gen­er­a­tions. The sub­pop­u­la­tion in Mon­go­lia is es­ti­mated to have had a 46% de­crease in pop­u­la­tion size since 1985, al­though exact pop­u­la­tion size was not iden­ti­fied in schol­arly re­search.

Be­cause of hunt­ing and other preda­tors such as wolves (Canis lupus) there is an ex­pected loss of 25-30 an­i­mals a year for the Mon­goloian sub­pop­u­la­tion. Based on these trends, the fu­ture of wild Bac­trian camels is ques­tion­able.

The ef­forts to con­serves the wild ver­sion is fo­cused on an iso­lated pop­u­la­tion in China/Mon­go­lia that doesn't breed with the do­mes­tic camels. Be­cause of the ge­netic dif­fer­ences be­tween the do­mes­tic and wild species, the lack of chances to hy­bridize is a major con­trib­u­tor to their con­ser­va­tion sta­tus. (Hare, 2008; Nowak, 1999)

Other Com­ments

The IUCN clas­si­fies the wild species of Bac­trian camel as Camelus ferus. In­ter­est­ingly, the do­mes­ti­cated form of this species is clas­si­fied as Camelus bac­tri­anus. Grubb (2005) con­sid­ers ferus a sub­species of bac­tri­anus. (Hare, 2008)

Con­trib­u­tors

Emily Cut­shall (au­thor), Rad­ford Uni­ver­sity, Karen Pow­ers (ed­i­tor), Rad­ford Uni­ver­sity, Tanya Dewey (ed­i­tor), Uni­ver­sity of Michi­gan-Ann Arbor.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

diurnal
  1. active during the day, 2. lasting for one day.
dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

food

A substance that provides both nutrients and energy to a living thing.

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

migratory

makes seasonal movements between breeding and wintering grounds

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nomadic

generally wanders from place to place, usually within a well-defined range.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynous

having more than one female as a mate at one time

scavenger

an animal that mainly eats dead animals

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

young precocial

young are relatively well-developed when born

Ref­er­ences

San Diego Zoo Global. Camel. 2013. Ac­cessed Sep­tem­ber 20, 2013 at http://​animals.​sandiegozoo.​org/​animals/​camel.

2012. "Camelus bac­tri­anus" (On-line). AnAge: The An­i­mal Age­ing and Longevity Data­base. Ac­cessed No­vem­ber 26, 2013 at http://​genomics.​senescence.​info/​species/​entry.​php?​species=Camelus_​bactrianus.

Ahmad, S., M. Yaqoob, N. Hashmi, A. Zaman, M. Traiq. 2010. Eco­nomic im­por­tance of camel: A unique al­ter­na­tive under cri­sis. Pak­istan Vet­eri­nary Jour­nal, 30/4: 191-197.

Chen, J., Z. Bai, C. Gao, J. Wang. 2009. Mor­phol­ogy of Rhi­nen­cephalon and Hip­pocam­pal for­ma­tion of the Bac­trian camel (Camelus bac­tri­anus) with their adap­tive fea­tures. Vet­eri­nary Re­search Com­mu­ni­ca­tions, 33/1: 25-32.

Cui, P., R. Ji, F. Ding, D. Qi, H. Gao, H. Meng, J. Yu, S. Hu, H. Zhang. 2007. A com­plete mi­to­chon­dr­ial genome se­quence of the wild two-humped camel (Camelus bac­tri­anus ferus): an evo­lu­tion­ary his­tory of camel­i­dae. BMC Ge­nomics, 8/241: N/A - open ac­cess jour­nal.

Elias, E., D. Cohen. 1986. Par­tu­ri­tion in the camel (Camelus drom­e­dar­ius) and some be­hav­ioral as­pects of their new­born. Com­par­a­tive Bio­chem­istry and Phys­i­ol­ogy Part A: Phys­i­ol­ogy, 84/3: 413-419.

Er­dun­chaolu, E., K. Take­hana, E. Ya­mamoto, A. Kobayashi, G. Cao, U. Baiyin, P. Tangkawat­tana. 2001. Char­ac­ter­is­tics of dor­sal lin­gual papil­lae of the Bac­trian camel (Camelus bac­tri­anus). Anato­mia, His­tolo­gia, Em­bry­olo­gia, 30/3: 147-151.

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