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  macio19981 26.11.2010 (19:51)

  The Djungarian hamster (Phodopus sungorus), also known as the Winter white Russian dwarf hamster, Dzungarian dwarf hamster, Russian dwarf hamsters, Siberian hamster, Winter white hamsters, and Sapphire winter white Russian dwarf hamster is a species of hamster in the genus Phodopus. They are typically half the size of the better-known Syrian hamster, and therefore called dwarf hamsters along with all Phodopus species. Features include a typically thick dark grey dorsal stripe and furry feet. The tail is so short that it hardly shows when the hamster is sitting. As winter approaches and the days shorten, Djungarian hamster dark fur is moulted and replaced with a coat which is almost completely white (hence the name). In the wild, this adaptation helps them evade predators in the snow-covered steppes of winter. In captivity this does not always happen due to hamsters getting confused by artificial light. They live mainly in Siberia and are also found in Dzungaria, Kazakhstan, Mongolia and Manchuria.
  
  The average lifespan of this species is 1½ to 2½ years.
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  Djungarian hamster are often found on the pet market, in Japan and Europe more so than in North America and indeed are rarely found in pet stores in Canada, although the majority of these hamsters will be hybrids between Campbells, which is generally bad as these hybrids are prone to a number of genetic diseases, and are polluting the pure lines that breeders in the UK in particular are trying hard to keep the pure lines alive. Care is similar to that of the Campbell's Dwarf Hamster although they are not so prone to Diabetes. Djungarian hamsters make good pets for teens or adults, not for younger children unless that child is particularly sensible and supervised by adults when handling their pet. They are usually more friendly to humans than other hamsters, and are less likely to bite. Due to a hamsters poor eyesight the risk of falling or jumping off your hand is high. Compared to other dwarf hamsters, they are also more aggressive and territorial to their cage mates. Djungarian hamster which could have some Campbells ancestry unless they are from showing stock (to National Hamster Council Standards) and should not be fed food containing sources of monosaccharides because of the risk of developing diabetes mellitus[2].
  [edit] Breeding
  
  In general, dwarf hamsters have more of a family structure than the Syrian hamster. However, this may be a result of a frequent confusion of the Djungarian hamsters and the Campbell's hamsters. Current research suggests biparental care in Campbell's hamsters (Phodopus campbelli) but not in Djungarian hamsters (Phodopus sungorus).[3] Some report that same-sex pairs and larger groups do not always get along well and frequent fighting may occur and be a great distress for them, or even lead to death. Most Djungarian hamster dwarf hamsters grow to 3 to 4" long. In the winter their fur turns almost completely white. They usually breed between April and September.
  [edit] Phases
  
  There are several phases (colorations) of Djungarian hamsters: their normal (dark brownish-grey colouring) or sapphire (blue-grey colouring). A white pattern called pearl (white with coloured hairs) sometimes exists in either phase, producing the normal pearl or sapphire pearl forms. However, these colours may be difficult to find, and the range of colours is much narrower than in the case of the Campbell's.
  
  Djungarian hamsters, also called Siberian hamsters, come from the steppes of Siberia and Kazakhstan and possess an adaptation not seen in Campbells: they can moult into a white winter coat. This camouflages them against the snow and also gives them their name. This moulting is brought on by the amount of day light; if the hamster is kept in an environment with is mediated through the nocturnal secretion of melatonin, the hormone secreted by the pineal gland. Short day lengths also triggers the regression of the gonads in both male and females, and thus Winter Whites become infertile. Because Winter White hamsters show such photoperiodic and seasonal changes in physiology and various behaviours, it is also used as a research model system for studying seasonality and photoperiodism.
  [edit] Campbell's/Djungarian hybrids
  
  Of the five species kept commonly as pets, only the Campbells and Djungarian hamsters are able to interbreed and produce live offspring (hybrids). Hybrids are most often unknowingly produced through incorrect identification of the two similar species of hamsters, and unfortunately the number of hybrids is increasing particularly within pet shops in many countries today where they are often mislabeled as being one or other of the pure species.
  
  Although hybrids make suitable pets, the breeding of hybrids should be avoided as it can cause health and birthing problems, and also the widespread breeding and distribution of hybrids could threaten the existence of both pure species in captivity. Therefore, if intending to breed Russian hamsters, it is important to ensure that both hamsters being bred are a pure form of and of the same species to avoid producing hybrids.
  [edit] Gallery
  
  Normal colouration.
  
  
  Pearl winter white—front
  
  
  Pearl winter white—side
  
  
  Pearl Winter White—Rear
  
  Pearl Winter White—Face
  
  
  Russian Winter White in a jar
  
  
  "Bull Winter White Shwi-shwi"

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