Djungarian hamster
The Siberian hamster (Phodopus sungorus), also known as the "Russian Winter White dwarf hamster" is a species of hamster in the genus Phodopu. They are typically half the size of the better-known Golden Hamster/Syrian hamster, and therefore called a dwarf hamster 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, the Siberian hamster's dark fur is almost entirely replaced with white fur (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. They are mainly found in Dzungaria, Kazakhstan, Mongolia and Manchuria.
Biology
The average lifespan of this species is 1½ to 2½ years.
Pet ownership
Djungarian hamsters 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 hybridized with Campbell's dwarf hamsters, which is generally undesirable 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 to preserve. Care is similar to that of the Campbell's Dwarf Hamster, although they are not as prone to diabetes. Djungarian hamsters make good pets for teens or adults, although they are not good with 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 their poor eyesight, they are at risk for falling from a high surface or from a handler's hand. Djungarian hamster may have some Campbells ancestry unless they are from showing stock (to National Hamster Council Standards). They should not be fed food containing sources of monosaccharides because of the risk of developing diabetes mellitus.
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). 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.
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.
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 breathing 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.
Roborovski hamster
Roborovskis (Phodopus roborovskii) or desert hamster is the smallest of all hamsters, averaging under an inch (2 cm) at birth, and (rarely) three inches (7.5 cm) during adulthood. Distinguishing characteristics of the Roborovskis are eyebrow-like, white spots, and the lack of any dorsal stripe (found on the other members of the Phodopus genus). The average lifespan for the Roborovski hamster is three (3) years, though this is dependent on living conditions (extremes being four years in captivity and two in the wild). Although claimed to be hypoallergenic, Roborovski hamsters have been associated with the development of asthma in previously asymptomatic owners.
Habitat and diet
Roborovski hamsters live in and around the Gobi Desert, throughout Mongolia's desert steppe and the adjacent territories of Kazakhstan, Russia (Tuva) and Northern China. Their efficient use of water makes them particularly suited to the steppe and desert regions they inhabit. Also they make very interesting house pets. They dig and live in burrows with steep tunnels as far as six (6) feet underground. In the wild, Roborovski hamsters are crepuscular, most active at dawn and dusk.
They are omnivorous, eating primarily grains, vegetables, fruit, and plants but will also eat meat and insects in small quantities. Roborovski hamsters remain underground in winter and survive the season by stockpiling food in warmer weather and storing it in special food chambers within their burrow system. Except they don't particularly like eating the pellets that are in most common hamster foods from convenience stores.
Breeding
The gender of a roborovski is determined as such: Female openings are very close together and may even look like just one opening, while male openings are further apart. Males usually have a visible scent gland near the navel, above the two openings appearing as a yellow stain.
Roborovski hamsters may reach sexual maturity as early as 5 weeks but usually do not breed until the year after they were born, usually early spring. It is advised when keeping them as pets that females should not be mated until they are closer to 4 months of age, males usually reach sexual maturity at 3 months. The gestation period of Roborovski hamsters is usually 20-22 days but can be up to 30 according to some sources. As the birth day grows closer the female will become more aggressive towards the male and often banish him from the nest till after the birth. It has been known that the female roborovski hamster can bite an owner if she is handled when she is heavily pregnant. Litters are usually small, being typically of 4-6 pups, though larger litters have been reported of up to 10. If the male is still around the female shortly after her birth he will attempt to mate with her again.
Campbell's dwarf hamster
Campbell's Russian dwarf hamster (Phodopus campbelli) is a species of dwarf hamster. It was discovered by W.C. Campbell in 1902 in Tuva, an area that has historically been geographically linked with both China and Russia. The Campbell's dwarf is also native to the steppes and semi-arid areas of Central Asia, the Altay mountains, and the provinces of Heilungkiang and Hebei in Northeastern China.
This hamster is sometimes referred mistakenly to as the Djungarian hamster (or Dzungarian hamster), or simply Russian, and often labeled as a Winter white Russian dwarf hamster. (See Winter White/Campbell's Dwarf Hybrids below.) In Tuva the species is called Pouched in the Tuvan language, referring to the well-known physical characteristic of most hamsters. There has been some debate over the classification of Campbell's dwarf and its closely related cousin, the Winter White, but now the two species are usually classified as Phodopus campbelli and P. sungorus, respectively. It has been claimed that the Campbell's hamster is less friendly in temperament (to humans) than the winter white and is consequently more likely to bite or nip.
The average lifespan of the Campbell's dwarf hamster is 1½ to 2 years, although they can live longer.
Habitat
In the steppes of eastern and central Asia, the Campbell's dwarf enjoys digging burrows which may extend up to three feet underground. These burrows are commonly lined with scavenged sheep's wool and dry grasses; the burrows maintain an average temperature of 62 degrees Fahrenheit (16°C). Natural predators include various owls, foxes, falcons, and weasels.
In captivity as pets, the use of heavily scented wood-based cage litter such as cedar can lead to itching, sneezing and even severe allergic reaction and should never be used. Cat litter should never be used since it contains chemicals that will be deadly to hamsters. Paper-based beddings are encouraged, with aspen shavings usually now being regarded as the only safe wood-based choice.
Commercial "fluffy" beddings, usually made of cotton or similar material, have come under some controversy as possibly being damaging to stomach or intestines if swallowed and can also get caught around the limbs of the pups causing deformity and even death. While paper-based or aspen bedding is used to give the hamster burrowing opportunities while providing odor control, plain toilet tissue is frequently recommended as a nesting material to be used in addition to the "ground cover" of bedding.
Multiple owners find that the use of bathing sand is helpful. Chinchilla bathing sand can be found in most pet stores, although chinchilla dust may cause sneezing and respiratory problems. Campbell's dwarves seem to particularly like cleaning themselves with sand, as the grains remove dirt and oil from the coat.
Cages should have at least 3 square feet (0.28 m2) of space per hamster, with one additional square foot per extra hamster. Wire, tube, and bin cages can be used. Campbell's hamsters may have difficulty climbing up big tubes due to their small size.
Breeding
Breeding Dwarf Russian Hamsters is much simpler than breeding Syrian Hamsters as they will live together in mixed sex pairs or groups and breed naturally. Pairs or groups are best established at a young age as introducing older hamsters can often result in fighting. Males will naturally mate with the females if kept together and when in season the female will allow the male to mount her. He will thrust a few times before dismounting and washing himself and then often will remount and mate again. The male will usually mate with the female several times. Not all unproven males will get a female pregnant after the first mating and some males may need to mate several times before a successful pregnancy occurs. The actual mating may not always be observed.
The gestation period of Dwarf Russian Hamsters is 18–21 days and if mating was observed then the time of the expected arrival of the litter can be roughly calculated. If mating was not observed then it is often not possible to know tell when the litter is expected. Many females do not appear pregnant until a couple of days before the birth but an increased aggressiveness of the female towards her mate, colony hamsters or humans is often an indication of pregnancy. The female will often banish the male or other hamsters from the nest a couple of days before pregnancy and/or after the birth. Therefore as soon as it is noticed the female is pregnant, it is best to clean the cage.
Females usually give birth during the evening, night or early morning but sometimes give birth during the day. The female is active right up to the moment of birth. Before giving birth to each baby, she tightens her abdominal muscles two or three times, then sits up and crouches over as she gives birth to a single baby within a couple of minutes. A placenta, which looks like a small red blood sac, may be released after the birth of each baby and this is normally eaten by the mother as it is a good source of protein. Babies are born at approximately 10-minute intervals and the mother may be active between each birth. Therefore babies may be born around the cage but the mother will usually collect them all up and place them in the nest when birthing is complete. After the female has given birth, there are often spots of blood on the bedding or around the cage. This is caused by the passing of the placentas and is normal and nothing to be alarmed about. Severe bleeding from the female, though, should be cause for alarm. The pups are born naked, blind and deaf, weighing only 3 grams. If the hamsters are to be dark-eyed, the eyes can be seen under the skin but if they are to be red-eyed, the eyes cannot be seen at birth. They are born with teeth which allow them to suckle. Their skin is transparent and, when they are fed, milk can even be seen in the stomach.
Social aspects
Unlike other hamster species, especially the Syrian hamsters, the male may play an active role in birth and rearing. He may assist the female in pulling pups from the birth canal, cleaning them, and ensuring the new mother has enough to eat. He may also guard them while the female is away from the nest. Since the pair is likely to mate again quickly, the male should be separated from the female before birth unless more pups are desired and the female is fit enough for a repeat pregnancy.
Like other hamsters, the Campbell's Russian dwarf will eat its young in certain emergency (or perceived emergency) situations, such as a protein deficiency in the mother or a threat toward the young. "Threat" may include anything from a predator (including a re-introduced father) to a habitat that the parent hamster does not believe will provide adequate size, covering, food, or water for its new inhabitants.
Unlike Syrian hamsters, Campbell's dwarfs are sociable and may be kept in colonies. If the hamsters are introduced at a young age, generally younger than eight weeks, they will often happily coexist in same- or mixed-sex groups. (Note that mixed-sex groups should be avoided as hamsters are lively breeders.) Contrary to some claims, the hamsters do not have to be related to live together peacefully. Some Campbell's dwarfs live together for long periods of time, such as over a year, only to eventually and unexpectedly end up fighting to the point of requiring separation. Pet owners should plan for the possibility of providing additional accommodations should this occur.
Campbell's dwarfs are crepuscular, meaning that they are most active at dawn and at dusk.
Winter white/Campbell's dwarf hybrids
Of the five species of hamsters usually kept as pets, only the Winter White and Campbell's dwarfs 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, such as mislabeling at a pet store.
Unfortunately, the number of hybrids is increasing, leading to a rise in health problems (such as the emergence of diabetes in the Winter White and glaucoma in the Campbell's Russian) and a decrease of pure species in captivity. Breeding of hybrids is discouraged, and the amount of accidental hybrid breeding and its repercussions underscores the cautions of casual breeding already expressed above.
0 comments:
Posting Komentar