The domestic rat is descended from the albino strain of the brown rat, which arrived in New Zealand during the nineteenth century onboard European sailing ships. Mice originated in the grain producing areas of northern Asia, gradually spreading to all parts of the world, today’s pet mice are descendants of the house mouse and come in a variety of whole and mixed colours. Rats and mice are very active and can be entertaining pets, rats in particular can become quite tame and enjoy human company.



Housing

It is best to house rats and mice in cages where they can be viewed from the front rather than the top, to reduce stress. Mice do not require expensive housing. A hardwood cage or a clear plastic container with a hinged lid is best. Purpose built housing for rats and mice are available from most pet shops. Make sure the cage contains a nesting or sleeping area that the rats or mice can retreat to. A suitable size cage for mice is 60cm x 30cm x 25cm while two rats can be housed in a 3ft x 18” x 18” cage, but a larger cage is better. Suitable bedding includes sawdust, woodshavings and shredded paper without ink, which can be toxic to rodents. Bedding helps provide warmth as well as nesting materials.




Social Grouping

Mice are social creatures and enjoy the company of other mice; it is best to keep 2-3 female mice together rather than many males as they may fight. A rat can be housed on its own as long as sufficient human company is available.





Exercise

Toys such as plastic tubes, small boxes, ladders and Ferris wheels will help to provide a stimulating environment for rats and mice. Providing something to gnaw on will help to keep their teeth sharp, you can use a small log or bone for rats, or a small bark covered log for mice.




Cleaning

Rats and mice generally use one special corner for toileting purposes, this area should be cleaned daily, replace any soiled bedding. All bedding should be changed 2-3 x a week, and cages cleaned and disinfected every 3-4 weeks. Ensure they are dried well.




Food

Both rats and mice have similar dietary requirements; they thrive on pelleted food. But you can also feed raw vegetables and fruit such as carrots, celery or apples. Oats, wheat and wholemeal bread can also be given. Put the food in gnaw proof bowls. Always provide fresh clean water in drinking sippers, the sippers should be cleaned at least once a week to remove any algae or bacteria.




Handling

Rats are generally easy to handle, be gentle, they may bite if handled roughly, pick rats up by either cradling or cupping them in your hands. Mice can be picked up by taking the tail firmly at the base while supporting the body with your other hand.




Reproduction

The female mouse (doe) carries her young for 19-21 days she can have between 6-14 young in one litter. Rats carry their young for 20-22 days and can give birth to 8-11 young. A male and female housed together can produce litters every 4-5 weeks; soon you will have a population explosion, so it is recommended that they be housed separately.



Health

Prevent ill health by maintaining good husbandry; provide adequate ventilation, clean cage conditions and a good diet.

Respiratory diseases in particular are common in rats and mice – coughs, sniffles, bronchitis and pneumonia; these can be caused by viruses or bacteria. Intestinal complaints can occur due to bad food and unclean feeding bowls. Scratching around the head and bald spots on the body can be a sign of mites.