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General Care of the Hamster


The common hamster is usually the golden or Syrian Hamster. This animal originated in the Southeast
Europe and Asia. The coat colors are variable with the longhaired teddy bear, cream, white, or cinnamon being the most common types. Hamsters are usually nocturnal which means that they are more active at night than day. Males weigh about 3 ounces (100150 grams), and females are usually larger in size.

The hamster should be kept in an enclosed area such as an aquarium with a lid as they like to try and
escape and explore. Their housing should be at least 12" high and with a solid floor. We do not advise pine shavings not from kiln-dried lumber, cedar, redwood, or any other aromatic wood shavings as bedding because they can cause pneumonia problems. Aspen shavings or paper bedding is preferred. There are many toys, exercise wheels, tubes, and other items for keeping the hamster busy. We recommend the open exercise wheels that have one side solid and a solid type floor where it is difficult to catch/damage a leg. They love to gnaw and tear up items. The habitat needs to have the ability for you to catch up with the hamster(s) and place it into a smaller container for cleaning. The very large habitats can be an issue with urine smell as rodents continually urinate as they move about and cleaning with a very dilute vinegar and water is not easily possible with some of these habitats.

Adult females should not be housed together as they will fight and sometimes cause abscesses (bite
infections) on the head and elsewhere. If the temperature drops in the room where the hamsters are housed they may go into “pseudo hibernation”; and they may not be as active. Hamsters are omnivores and should be fed a commercial hamster, rat, rodent or mouse diet. They normally will eat about 57 grams of food daily. The hamster is a little different than mice or rats in that the hamster can ferment food in their fore stomach. As a general rule hamsters and other pocket pets should not have seeds or especially fruit as over 5% of their diet. Feeding vegetables can be up to 10-15% of the diet. Fresh water should be provided at all times especially if the female is in lactation.

As early as 78 weeks of age a female hamster may be able to breed. It is best to wait till the female is 45
months of age before you breed her or allow her to be with a male. Always take the female to the male’s cage as the female may fight to protect her territory. Introduce the female to the male in the early evening when the nocturnal hamster is ‘waking up”. If they don’t fight by the time you go to bed then you can leave them alone till morning. Remove the female to her own cage the next day. A white discharge is sometimes noticed from the vagina of a female in estrus (heat) and this is normal. Normally 12 hours of light is required before the female starts to show signs of estrus. Pregnancy lasts about 16 days. On average 410 pups are born. You should not disturb the female for the first 5 days after she has given birth or she can become cannibalistic towards the litter. The baby’s eyes should open up around 1012 days. You should feed the pregnant or nursing female as much food as she wants to eat. Weaning of the babies, also called cubs, should occur at about 21 days of age and to prevent them from breeding.
A phenomenon we sometimes see in rodents and ungulates (cloven-hoofed livestock) is
chromodacryorrhea. Chromodacryorrhea is a medical term for red tears. This redness is from a chemical
porphyrin secreted from the animal’s harderian glands near the eye. Porphyrin will fluoresce under a black light, while blood will not. Chromodacryorrhea can be due to sickness or a response to stress.
The common Syrian hamster has a scent gland located on the side of their flank. These glands may be
enlarged, and sometimes this is normal. Males may lick at these flank glands, also called hip glands, and cause wetness, which still can be normal. In the dwarf species, these glands are usually on the underbelly and single. The smell of this territorial-marking gland may be more noticeable in the dwarf species and female Syrian hamsters.

If your hamster develops diarrhea please call us. With all animals, we advise fecal examinations of their
stools. “Wet Tail” is a common name for a hamster that has diarrhea; it is only a sign and not a diagnosis of a specific disease. Other pocket pet owners may call their rabbit, chinchilla, gerbil, rat, or mice with diarrhea as having a wet tail, and the wet tail terminology is usually reserved for hamsters only. Contrary to belief stress alone rarely causes “wet tail”. Wet tail is also called proliferative ileitis. If there is diarrhea please bring in 10-12x stool samples for a fecal test, stains, and possibly cultures and other tests. Collect the stools in a zip lock bag and during weather of 50+F at night you can leave the sample outside the clinic 24/7 for when we go into the clinic the next day. Do not refrigerate these feces. Should your hamster be drinking more water and/or urinating more than usual, please call us regarding the collection of urine; the average 100-gram hamster should drink 8- 10 ml (1/3 of an ounce) of water a day. You can place the hamster in a smooth bottom, large storage-type container and suck up the urine in a syringe we can provide. One also can collect urine by placing plastic wrap under the wire cage. The average hamster lives 23 years.

Diets with seeds; not recommended
Carefresh complete for hamsters and gerbils
We recommend a pelleted diet because they are complete diets. If you look at any dog, cat or even poultry diets they take that extra step to pelletize the diet for a very good reason. Hamsters eating a diet with seeds in it will only eat specific seeds and not always the whole selection of seeds, let alone the vitamins or minerals which have been sprayed onto the outside of a seed hull that thus needs to be eaten.

Hamster, miscellaneous concerns
The outside cheek areas (commissures) can have a dry skin and be normal in some species (i.e. Russian

Cheek pouch impactions are due to food staying in these storage areas too long. The rotting material is
what causes the foul odor. We can clean out these pouches and have you use a Q-tip with a dilute disinfectant and/or antibiotics in the water but it is important to realize that this patient needs to be allowed to run out of food daily. Feeding only at night and ensuring there is no food in the morning is adequate unless there is weight loss. Some species, such as the Russian hamster, seem to have more of this problem. If the problem keeps reoccurring there is a surgery to remove/amputate the pouch and sew that area closed, yet the medical and environmental treatment is preferred. Hamsters are storing this food to take home to a secure place, and if there is no such hiding place they keep the food in their check pouches. If we are replacing prolapsed cheek pouch (eversion) we will place a suture knot outside the cheek.

Most hamsters are not fed a complete diet. A seed diet is poorly balanced. Hamsters on a complete
diet/laboratory animal rodent chow usually will have fewer age-related problems such as heart disease and amyloidosis in the kidneys. Heart problems and atherosclerosis are common if they are on a seed diet.

A fecal is an important test to help keep a hamster healthy, besides a proper diet. If we have an intestinal problem such as IBS-like signs we prefer a diet change over the prednisone/cyclosporine alone or in combination as there are side effects. Prednisone may raise blood sugar which may contribute to dysbiosis.

Hepatic fluid cysts are commonly found on an ultrasound or necropsy in a hamster. They are congenital
and are not a concern. There can also be fluid cysts on the epididymis and seminal vesicles.

Lung problems are commonly due to ammonia buildup from the bedding/urine.

Swollen feet can be done to bring on improper bedding such as aromatic wood shavings or some type of
contact irritant. Treatment with antibiotics and sometimes pain relievers, plus in all rodents with any
sickness problems we recommend a fecal sample and a urine test.

Polyomavirus is commonly seen in the Syrian hamster. Weight loss, trouble breathing, and death
are the signs that can occur with any sickness. About 1 in 10 hamsters with polyomavirus (HaPyV) have eye and other masses called trichoepitheliomas; this is because the virus targets the hair follicle keratinocytes and other cells and organs. Over 3/4 of the infected hamsters will die. Since there is no treatment depopulation is recommended. We have other handouts on infectious rodent diseases.
Renal amyloidosis can contribute to high blood pressure.

Many females will also have reproductive tract disease which may be subclinical (the owner may not notice cycling, or discharges). Many hamsters are so inbred that their life span is even less than the published 18-24 months seen before 2000.

The most common hamster skin diseases are ringworm and itchy skin diseases caused by parasites
(Demodex), cutaneous lymphosarcoma (a type of skin cancer) and hyperadrenocorticism (hair loss). There is a gland in the umbilical area that may open up and look like a waxy/cyst-like pocket. This umbilical area scent gland can be impacted or sometimes it can be a cancer. Sometimes these umbilical area glands are called ventral scent glands. There are also flank/inguinal scent glands which are more in the skin than below it and thus a color change is normally seen. Wet tail is also a skin problem, yet actually is due to diarrhea.

Rodents commonly have exceptionally large testicles for their size; this is normal and they are not
testicular tumors unless one testicle is much larger than the other. Chinese Dwarf Hamsters can have very large testicles that almost look like a double internal prolapse of organs. These testicles can be as large as the head of the hamster, and there can be some smaller 1/8″ or so double masses that look like small testicles. (This hamster is not truly a dwarf).

Tumors are common in rodents. If a hamster has a tumor and she is older than 6-12 months the outlook
is poor. A pet Syrian hamster that has not had a fecal to look for parasites such as tapeworms or bacterial intestinal infections such as Clostridium or Lawsonia can have a type of weakness and immunosuppression. If she was on a seed-based diet she may have atherosclerosis/heart disease and fatty liver concerns for anesthesia.

Most of these tumors are fast-growing, invasive, and respond poorly to any therapy including surgical excision.

With surgery on hamsters, they do not leave the incision site alone and Elizabethan collars are needed (and they still may chew the collar into pieces).

The vaginal area has many glands near it and the urethral opening. When there is a swelling/vaginitis-like problem going on this is a possible cause, especially if the discharge has a fetid odor. We need to do a fecal and urinalysis, and we may start the treatment with sulfadimethoxine antibiotic and meloxicam as a pain reliever for the swelling. For a creamy white discharge from the vaginal area, this can be normal.