Syrian hamsters are usually housed singly because of their inevitable aggressiveness toward each other. Dwarf hamsters can be housed in pairs.

The sex of adult hamsters is easy to determine. Males have very large, hard-to-miss testicles!

Male hamsters can smell more than female hamsters - but personalities vary from hamster to hamster.

Proper housing is a major factor in maintaining healthy hamsters. Wood and similar materials should not be used to construct enclosures because they are difficult to clean and cannot withstand the destructive gnawing of rodents. There are many durable coloured plastic enclosures on the market that include attached horizontal and vertical tubes through which the hamster can crawl for exercise.

One reference recommends at least 20 square inches of floor area per hamster, and a cage height of at least 6 inches. Hamsters seem to do best when housed in enclosures with solid floors, relatively deep bedding, and abundant nesting material. Shredded paper, wood shavings, and processed corncob are preferred bedding materials.

Cages and toys should be cleaned and disinfected weekly, with water and food bowls changed daily.

The enclosure must be built so the hamsters cannot escape. This is an especially important consideration because hamsters are proficient ‘escape artists’. In fact, once free it is a real liability because it will chew and gnaw on electrical and telephone cords, and household furnishings.

Good-quality food and fresh, clean water must be readily available at all times. The exact nutritional requirements of the hamster are not known. In the wild, they are omnivorous, feeding on plants, seeds, fruits, and insects.

Pet hamsters are best fed commercial rat or mouse diets. These foods are usually available as dry blocks or pellets. These commercial diets can be supplemented with small amounts of dry, sugar-free breakfast cereals, whole-wheat bread, uncooked pasta, cooked chicken, tuna fish, cheese, fresh fruits, and vegetables. The last two items must be thoroughly washed to avoid exposing pet hamsters to pesticide residues and possible bacterial contamination.

Pet stores sell prepared hamster diets available in boxes or bags. These diets contain large quantities of seeds and items rich in oils. Consequently, if improperly stored, they become rancid and lose their nutritive value. Furthermore, these oil-rich items promote obesity. These types of foods can be offered as a supplement to the commercial rat or mouse diets mentioned above.

All food should be provided in heavy ceramic bowls that resist tipping. The sides of the crocks should be high enough to keep bedding out of the food.

Water is most easily made available and kept free from contamination by providing it in one or more water bottles equipped with ‘sipper’ tubes. Make certain the ends of the tubes arepositioned low enough to the hamster easy access to them. Also make certain that very young hamsters are strong enough to obtain water from these sipper tubes.

Hamsters are primarily nocturnal (night-active), though they may exhibit relatively short periods of activity throughout the day. During their active period, hamsters eat and exercise - they seem to especially enjoy exercise wheels.

Hamsters have very poor eyesight, so they have to be supervised carefully when out of the cage - they are known to fall off the edge of tables and can be easily injured. Supervise children in particular very carefully with hamsters, as they don't tend to hang-on to the person holding them, so can be dropped easily.

Hamsters tend to be affected by relatively few naturally occurring diseases. Although some more unusual varieties of hamsters tend to be much more susceptible to disease and sensitive to antibiotics and other drugs than golden hamsters.

Hamster owners must be constantly vigilant for signs of illness and must seek immediate veterinary assistance when illness is suspected. Sick hamsters often become irritable and frequently bite. They are usually reluctant to move about and walk stiffly when forced to do so. Their eyes often look dull and sunken, and frequently have a discharge. Sick hamsters often stop eating or greatly reduce their intake offood. Consequently, weight loss is a common sign (not necessarily an easy one to recognize) of illness in hamsters.

You should also look out for teeth problems. The incisor (front, gnawing) teeth grow continuously for the life of the hamster (this is true for all rodents). They receive continuous wear as the uppers and lowers contact each other, preventing overgrowth. Misalignment of either the upper or lower incisors may result in overgrowth of one or more of the teeth. Overgrown incisor teeth usually cause serious injury to the roof of the mouth. Initial signs of this problem are drooling, lack of eating, weightloss, and eventually a foul odor from the mouth. You will need to visit a vet immediately to have the teeth clipped and they will probably prescribe antibiotics to prevent infection.

Hamsters are easily injured. They are frequently dropped while being handled (especially by children) or after they bite. Pet hamsters allowed ‘free run of the house’ (even for very short periods) are often stepped on or kicked and seriously injured or killed. Hamsters are frequently injured while inside an "exercise ball". This is a clear plastic sphere that the hamster can trundle round the floor. Injuries occur when a person accidentally kicks the ball or when it falls down a flight of stairs. Hamsters often perish when they are forgotten and left in these devices without food and water. Hamsters should be supervised in play balls at all times.

Although relatively rare, hamsters can and do get sick - they can suffer from bladder stones, cancer, abscesses (from infected cuts), 'wet tail', salmonella (from infected fresh food), mites and other illnesses - if you suspect anything is wrong with your hamster, visit the vet as soon as possible. If you get to know your hamster, you will know what is 'normal' and notice quickly when things are amiss.

Finally, a note to always check that the water bottle is working properly - change the water daily and make sure the hamster is managing to drink ok. Keep bedding clear so that it can't clog and drain the bottle.

Pet shops up and down the country are usually full of hamsters - so the first consideration should always be how you'll find new homes for up to 13 babies.

You should also be extremely knowledgeable about hamsters and it certainly isn't recommended for beginners. As hamsters can fight, breeding can be more tricky than with many rodents, so a lot of research is necessary first.

If you have been unfortunate enough to buy a pregnant female, the information below is designed to give you some emergency information - please research more on the internet, and speak to people who own and breed hamsters for more advice.

Pregnancy lasts only 15-16 days. Before delivery, the female becomes restless and usually discharges a small amount of blood from her vulva. Litters usually range from 5 to 10 pups. The pups are born hairless, with cars and eyes closed. They do, however, have their frontteeth (the incisors) at birth. Female hamsters with young must be provided with abundant nesting and bedding materials and plenty of food and water. They must not be disturbed in any way. The young should not be touched or handled until they are at least 7 days old, the nest should not be disturbed and the cage should not be cleaned during this period. Young hamsters usually begin eating solid food at 10 days of age but are usually weaned at about 3 weeks of age. Solid, pelleted food must be soaked to soften it and be placed on or near floor level of the enclosure for easy access by the weanlings. Sipper water bottles must be positioned low enough so that the smallest pups can reach them. Some pups will not be strong enough to extract water from sipper tubes, so owners must be vigilant for this potential problem and provide an alternative water source for them.