by Susan Leck, DVM, Dipl ABVP-canine & feline
Edited by Susan Horton, DVM

Domestic mice, Mus musculus, are primarily raised in captivity for the pet trade and as food for reptiles.  They are available in colors from white and tan to brown and black.  Outbred and inbred mice are used for research purposes.

Pet Appeal and Behavior

Mice are easy to keep as pets because of their very small size and their minimal requirements for space and attention.  Although naturally timid, a significant bond with humans may be formed with daily interaction and regular gentle handling.

Mice may bite if they are handled roughly or startled and may become aggravated when restrained.  Mice are territorial: males will initially fight when placed together, and females with litters may defend their nests.  Mice that have been housed alone are more likely to fight when introduced to other mice.

Housing Recommendations

Mice can thrive in captivity as long as they are not overcrowded or overheated.  The minimal size enclosure for one adult is 24″ x 24″ x 12″ high (61 x 61 x 30 cm).  Females with litters require 2-3 times more space.  The enclosure must be able to accommodate a nesting area, feeding area and exercise wheel.  It must be escape proof with a secure lid.  Glass aquariums are not recommended, because they can overheat rapidly on a warm day and can kill a mouse.

Suitable substrates include shredded paper (non-inked), recycled newspaper composite materials or pellets.  Cedar chips should be avoided, as they may be toxic.  Substrate should be changed once or twice weekly in order to keep the cage as odor free as possible.  Additional materials (e.g., paper towels, socks, mittens) may be added to the enclosure for nesting.


The recommended diet for domestic mice is a commercial pelleted mouse feed (greater than 14% protein, ideally 20-24% protein).  Breeding adults and youngsters may require additional calories.  Pellets may be softened for baby mice, which will begin eating them around 2 weeks of age.  Seed diets are not recommended: mice are often victims of obesity, starvation and malnutrition from all seed diets.

Sipper tubes or water bottles may be used.  The water must be changed routinely and the tip checked to ensure it is flowing and free of obstruction.


The mouse may be grasped by the skin at the base of the neck and the base of the tail for restraint.  Grasping the tip of the tail may cause degloving.  A mouse may be accustomed to climbing onto hands, but one must ensure that it does not jump and fall off.

Common Disorders of Domestic Mice

  • Obesity
  • Ectoparasitism
  • Epizootic diarrhea of infant mice
  • Alopecia
  • Barbering
  • Chronic respiratory disease
  • Pinworms
  • Neoplasia
  • Malocclusion
  • Heat stress
  • Viral infections
  • Malnutrition
  • Trauma, bite wounds
  • Toxicities/poisoning
  • Giardiasis
  • Salmonellosis
  • Mouse pox

What Every Owner Should Know

  • A child should not be responsible for the feeding and care of a pet mouse.
  • Small children may handle the mouse too roughly or drop it, resulting in trauma.
  • Common household dangers include predators, such as dogs, cats, and ferrets.
  • Mice can be escape artists, so the enclosure must be secure.
  • For activity, mice like to explore tubes, gnaw on items and run in an exercise wheel.
  • Mice should be prevented from accessing pesticides and other toxins.
  • They should be protected from overheating.

​If you have any questions, please feel free to call us at (502) 241-4117.