Taking Care of your Rat
Adapted from Susan Leck, DVM, Diplomat ABVP(canine and Feline Medicine)
GENERAL CHARACTERISTICS
Pet rats are of the species Rattus norvegicus. These nocturnal rodents are characterized
by elongated bodies, short fur, small eyes and ears, and hairless tails. Common
Strains/variations of pet rats include albino (white) rats, Dumbo rats, sphinx rats
(hairless), silky rats, hooded rats, and many more. Rats can make great pets because
they are easy to care for, have very little odour, and rarely bite. They are affectionate
and intelligent animals that quickly bond to their owners.
Anatomically, rats have open inguinal canals, a diffuse pancreas, a divided stomach, a
large caecum, and an os penis. Rats do not have gallbladders and cannot vomit. Albino
rats have poor eyesight, and all rats depend on whiskers and scent for sensory input,
sometimes weaving their heads back and forth to focus on objects. The red brown
Harderian gland is a lachrymal gland located behind the eyeball; this gland produces a
lipid and red porphyrin-rich secretion. In illness, red tears may overflow and stain the
face and nose, and can also be spread or caked on wrists, ears and fur. There is no
blood in this tear film and the red crusts will fluoresce bright under ultraviolet light. As
rats age white hair coats can take
on a yellowish cast.
Because rats are social and need
companionship, they should be
maintained in same sex or altered
sex groups. Suitable bedding
materials include shredded paper,
recycled newspaper composite
materials or pellets. Pine and
cedar should not be used as litter
because they are toxic to the
animals. Bedding should be a
minimum of one-quarter to one
inch deep and changed at least 1
to 2 times per week. The housing
should be escape-proof, wire mesh
with plastic or metal solid flooring
and should be large enough to allow nesting, burrowing, and exercise areas. Exercise
may be provided in the form of a large exercise wheel and climbing toys. Minimal
enclosure size guidelines for one adult rat are 24” X 24” X 12”high (with a secure wirescreen clamped top or other “roof” to prevent escaping).
Most rats will allow you to pick them up by placing the hand firmly over the back and rib
cage, or by scooping them up in both hands. The head can be restrained with the thumb
and forefinger behind the jaws. Scruffing the loose skin at the nape of the neck can help
restrain and active rat, but many rats object to this.
Male rats have a scrotum, making them easily differentiated from female rats. The
anogenital distance is roughly twice as long in males as in females. Rats are communal,
and males and female may be combined in a solitary, uncrowded enclosure for breeding
purposes. Young are raised communally with shared nursing responsibilities. If a
female is not bred by 8 months of age, her pelvis will fuse and she may have difficulty
giving birth later. Spaying may help prevent mammary tumours, which are relatively
common. Pictured below is a male scrotum (very young).
Rats are omnivorous rodents. Many rat/rodent pellets are available commercially; these
foods provide a complete diet. Sometimes small amounts of fresh fruits and vegetables
are added. Adults require 5-10 gm of pellets per 100 gm of body weight daily and 10ml
of water per 100 gm of body weight daily. Treats and seed-based diets are not
recommended as they do not meet nutritional requirements. Fresh water should be
available at all times, ideally provided via a drinking bottle or sipper tube. Rats may be
suspicious of new foods that are introduced, so care must be taken to ensure the rat
continues eating if a new brand of pelleted diet is offered.
Rats can have severe dental problems. Difficulty eating or dropping food may be signs
that your rats teeth are misaligned. Infection or trauma can cause the incisors not to
meet properly. Since these incisors continually grow, they will become quite long. We
can help with this problem.
What you need to Know

Life Expectancy is two to three years

Room temperature 65-80 degrees F (average 72F) with 40-70% humidity is suitable
environment

Keep housing clean to minimize respiratory disease risk.

Dogs, cats, and ferrets are predators.

Basically nocturnal, but can be active during the day as well.

Monitor faeces and urine output

Need at least 30 minutes each day for an exercise/play with owner.

Bite aggressively only if restrained against their will.

Often difficult to litter-train (faecal).

Feed pelleted diet, not seed diet.

Monthly examinations of weight, teeth, nails, and lump checks recommended.
Pictured below are some examples of proper housing for rats.
At Aston Clinton Veterinary Centre, we do routinely spay and neuter rats to ensure a more
peaceful colony. Some people suggest spaying may help reduce the incidence of mammary
cancer as well. Mammary cancer is a common problem with rats. If a lump appears
anywhere on your rat's body, please have us check it out. These masses can grow to
amazingly large sizes quite quickly. They are usually safe and easy to remove when they are
small. Feel free to ask us about these services.