Domestic Rat

Rattus norvegicus

Order: Rodentia

Husbandry Information

Housing Requirements

  • At the Seneca Park Zoo we house our rats socially. However, we only ever house females. So I am not sure what would happen if males were housed socially. The social housing works well and the rats often sleep together in a group. The exact space requirements we use for your rats is based on the number of rats we have and their physical size. Generally we house 3 large sized rats in an enclosure that is It is important to provide enough space for walking and climbing. This is about 18″ wide x 30″ long and 30″ tall.
  • Because of respiratory problems it is important that rats are kept in open air cages. Aquariums do not allow proper ventilation. In addition, the use of a substrate such as yesterdays news is better for respiratory problems opposed to wood chips. A bedding layer of two to three inches is good enough to allow digging
  • Rats should have a hiding spot. Either a small house, or a cardboard box which they can go into. It is important to provide materials that the rats can nest with, such as shredded newspaper, hay, straw, paper towel or something similar.

Diet Requirements

  • In the wild, rats will eat anything they can find.
  • In captivity, rats are fed rodent blocks and carrots. In addition to the rodent blocks, rats can be fed a variety of root vegetables and greens. Sunflower seeds can be offered in small amounts.
  • Because rats are omnivores, even pet rats have enough predatory instinct left in them to consider birds, fish and even some smaller rodents as “snacks.” This sometimes causes strife when pet rats eat other smaller pets in a household.
  • At ZooAmerica, we have two female dumbo rats. Due to some initial fighting, we have had to change their diet slightly. They receive rat chow ad lib, and for variety, they get a small amount of additional food daily (vegetables, fruit, mealworms, peanuts)

Veterinary Concerns

  • Most domestic rats carry dwarf tapeworm which is a zoonotic disease and very difficult to get rid of. Hand washing after handling is very important for this reason.
  • Treat rat bites seriously. Many rats harbor a bacteria that causes an illness called rat bite fever. Look at the CDC fact sheet on this illness for more information. CDC Facts on Rat Bite Fever

Notes on Enrichment & Training

  • Shredded newspaper or something similar along with a hiding space (line a small cardboard box) encourages the natural bedding behavior, or the “pack rat” behavior.
  • Rats also seem to do better when housed socially. If not housed socially, there should be daily contact with the animal.


Colony or Breeding Management


Individual Identification


Programmatic Information


Temperature Guidelines



Tips on Presentation

  • Zoo Atlanta: We train our rats to enter a kennel from their enclosure and then remove from the kennel for programs. We allow them to move freely on our hands/arms during programs and then hold them in a seated position with tail tucked under the body to present them for touching. We always take at least two rats on program together (even though we might only present one) and have two at home so no one is never alone. If we have a group of 3, then the whole group goes together. We have found that the most common time handlers get bit is when they are trying to search for rats in their home enclosure as often the rats are hiding and handlers accidently stick fingers into faces.

Touching Techniques

Tips on Handling

  • Being an animal that is easily trained, rats are extremely easy to handle on programs. Some people many handle 1 at a time, while others may handle up to 4.
  • They are very good at climbing and if you form a cradle with your front two arms they will climb from your arms to your should and back.
  • Be careful you do not have loose clothing. They are very good at getting into open pockets or loose sleeves.
  • Because of the risk of salmonellae, precautions should be taken if allowing visitors to touch them. Do not allow those that are immuno-compromised, under 5 or over 65 touch rats. Those that do touch should clean their hands with sanitizer after.


Potential Messaging

Acquisition Information

The Philadelphia Zoo has acquired domestic rats from many sources in the past: feeder animals, pet stores, and private breeders. Rats from domestic breeders tend to work better as program animals. Private breeders have a lower volume of animals than pet stores, and breeders spend time handling and socializing their animals when they are young. Consequently, the rats are already pretty tractable when they arrive at the zoo.

Currently, Greensboro Science Center has a number of surplus Long-Evans hooded rats they are looking to place. This is an outbred strain and is far more resistant to mycoplasm and cancer strains that have afflicted pet store rats. Consequently, they tend to have a longer lifespan. They also generally have very docile personalities.

Comments from the Rating System

  • Maryland Zoo in Baltimore: Care and handling are typically easy, but longevity is an issue.
  • Philadelphia Zoo: Common but misunderstood; good example of a recommended pet; VERY trainable
  • Roger Williams Park Zoo: Short life expectancy
  • Seneca Park Zoo: Short life span
  • Woodland Park Zoo: Easy to train. Short life span.
  • Roger Williams Zoo: get them as young as possible (weanlings) and be sure they’ve been handled a lot.

Natural History Information

Range and Habitat

Rats can basically be found anywhere there are people. In the wild, rats dig burrows to live in. Because they are good swimmers, they can often be found inhabiting sewers.

Physical Description

Domestic rats come in many different color patterns, from dark brown to spotted and silver. There are also different breeds of domestic rats, or fancy rats, including, rex, odd-eye, hairless, tailless, satin and standard. Rats have long tails with little hair; a rat’s temperature is regulated though its naked tail.
The average weight for a domestic rat is one-half to three-quarters of a pound; from head to tail, they are 14 to 18 inches long. Males are generally larger than females.

Life Cycle

A pregnant female will not build a nest until the day before or the day of she gives birth. After a gestation period of 21 to 23 days, she will give birth to 1 to 22 pups (average litter size is 12.) Although she only has 12 nipples, a female can care for a larger litter as long as she is getting proper nutrition; she simply splits her brood into two groups and alternates feeding each group. Rat pups wean at about 5 weeks of age.
Average lifespan is 2 to 3 years.


Rats are social creatures that will establish an order of hierarchy within the group.
They are nocturnal.
Rats have poor vision. To compensate for this, a red or pink eyed rat will often weave its head side to side to add “motion” to see better. They don’t see in color.
Instead of purring like a cat, a happy rat will chatter or grind its teeth. Often, chattering teeth results in “vibrating” eyes, caused by the lower jawbone pressing the backs of the eyes. This is a good sign, regardless of how silly it looks.

Threats and Conservation Status

Rats have no conservation status; in fact, in many areas, rats outnumber humans.
Domestic rats are prey to almost any predator that is larger than them. However, when domestic rats are raised with other domestic pets (dogs, cats, etc.) they will develop a bond with the other pets in the home with no problems. Rats in the wild are just out of luck.

Did you know…

  • The word ‘rodent’ is derived from the Latin word ‘rodere’ that means ‘to gnaw’.
  • Domestic rats are very popular as pets and even have breed standards like dogs and cats.
  • Although the black rat played a part in the plague, it was not the rat itself that carried the plague but the fleas on the rat that acted as the vector.
  • Giant pouched (or Gambian) rats have been trained to sniff mines and for TB outbreaks in Africa.
  • Domestic rats are descended from the brown or Norway rat.




Contributors and Citations

  • The Philadelphia Zoo
  • Saint Louis Zoo