Fancy Care Guide

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Mice need to be fed and watered every day. A plastic or glass water bottle can be hung through bars into the cage, or attached inside the tank using either a bottle holder or sticky-back velcro strips. Mice need access to a source of water at all times. Bowls are generally not recommended. Mice will kick bedding into the water or foul it with waste in very short order. They dehydrate very quickly and a day with no water for a mouse can be a death sentence. If you find your mouse is behaving oddly or looking off, the first thing you should do is make absolutely sure the water bottle is working.

Mice have many commercially-available foods designed for them, and some owners choose to mix their own feed. Commercially-available food comes in either pelletized (often called lab block) or seed mixes. Feed mixes for breeding animals need to have a higher protein percentage than feed mixes for pet animals. Some breeders use small amounts of kibble designed for cats or dogs in addition to the mouse’s regular feed in order to increase protein consumption.

Avoid feeds that list hamsters, gerbils, or other rodents on the package, though mice and rats can usually eat the same foods. In general, a mouse’s digestive tract is geared toward grain seeds like oats, wheat, and barley, with a little seed like flax, pumpkin, or sunflower and occasional bugs for protein, particularly mealworms. Homemade mouse mixes that contain mostly these kinds of foods do well to provide for a mouse’s diet. Be wary of those that include large amounts of seeds or human foods.

The majority of breeders do use pelletized foods like Mazuri, Kalmbach or Harlan Teklad, and the breeder of your mice can give you more information about what that line of mice will be used to.

The last thing a mouse needs to get by is a source of enrichment. Even laboratories accept that mice need an enclosed shelter inside their caging to use as their nest. Anything from a purpose-made little igloo to an empty tissue box with the plastic removed will do just fine. Mice do love to shred cardboard, so cardpaper boxes and tubes are a favorite. The cardboard provides a hiding place until it is shredded into little pieces of nesting.

In addition to their house and a tube, some mouse breeders and owners include a wheel for exercise, especially for lone males. Wheels advertised for mice are almost always too small, so see how large a wheel you can fit into the cage. A too-small wheel causes a mouse to develop “wheel tail” in which the tail is permanently and painfully curled up over the mouse’s back.

Metal wheels can be squeaky and difficult to clean, while plastic wheels tend to accumulate urine build-up and can be chewed. Wheels with bars can trap the feet or tails, causing injury, and solid plastic wheels are a way to avoid this.

Saucer-type wheels, in which the mouse runs atop a spinning disc instead of inside a wheel are an excellent way to avoid wheel tail or injury while using very little space. They are very safe. There is also a mouse hut designed with a saucer wheel on the roof, often used in laboratory cages which have a premium on space.

Other forms of enrichment like branches, ladders, and other places for mice to climb or hide can add more interest to the cage. Always be careful about toxicity of things not designed for mice, especially if they came from outside. Fruit wood and oak are generally safe, as are items designed for birds. Items designed for reptiles and fish are often safe, though soft plastic plants are quickly destroyed. Any kind of thready fabric can be a danger, as loose threads can wrap around small limbs and cause injury. Thread-less fabrics like fleece are much safer, and some owners keep hammocks or other fabric toys in their mouse cages.

Before you bring new mice home, make sure you have their new home ready. Groups of females up to around 4 can be kept in 10 gallon aquariums with mesh lids, or larger groups in a 20 gallon long. Solid-walled caging like aquariums need to be no taller than 12” in order for the mesh lid to provide sufficient air circulation.

Many mouse owners use homemade cages made from large Rubbermaid-type tubs, adding fine wire mesh to the sides and lid for ventilation.

Bar cages need to have very close bars, as a mouse can easily escape if there is even one gap large enough for their skull to fit through. Quarter-inch bar spacing is usually sufficient for adults, though baby mice may be able to escape. Bar cages are not recommended for maternity housing for this reason.

Hamster-type cages of solid plastic are generally considered very bad for mice, as they are chewable, hard to clean, and have insufficient ventilation.

The general floor spacing rule backed by scientific research is 50sq in to 100sq in per mouse. This can give or take dependent on line and stress levels.  

Here is a simple brake down of aquarium sizes vs how many mice they should be housing comfortably.

• 10 Gallon - 1 Male or 2-3 Females

• 20 Gallon - 4-6 Females

• 30 or 40 Gallon Breeder - 7-12 Females 

This is a generalized list to show how the adverage mouse is housed. Some of our lines specifically can handle fewer numbers in larger enclosures please feel free to ask us about lines that may be able to handle larger spaces more effectively.

Anything larger is highly not recommended! This is due to airflow issues in tanks taller than 12in. Groups of females 13 and larger tend to have hierarchy issues so we also strongly recommend groups of 12 or less to be kept together.  

The enclosure needs some bedding in it, too. Aspen, Pine or Hemp are all a fairly safe choice in wood shavings, providing a fluffy material without the dangerous oils in cedar. Sanichips are a very finely cut aspen flake that dries more quickly but does not have the fluffy quality. Avoid paper, softwood, conifer, and cedar bedding. These have been proven to be dangerous to small animals.

Each of these has its advantages and disadvantages, with some cheaper, some keeping the cage drier, and others helping to minimize odor. How frequently the bedding needs to be changed will depend on the number of mice for the space, which bedding you use, and how much ventilation they have.

HowRemove them from their cage and place them in a pet carrier or a safe, enclosed area

Take out any toys or tunnels and clean them if necessary

Take out soiled and wet bedding with a dustpan and brush or simply dump out of possible.

Then wipe it all down and wash thoroughly with warm water and white distilled vinegar.

Leave to air until completely dry.

Clean their food bowls and their water bottle, using warm water and a bottle brush

list of items marketed toward mice and other small rodents that are actually very unsafe.

Paper bedding such as carefresh - can use for nesting materials but is *not safe* as actual bedding when used alone or as a majority of the bedding mix.

Wheels marketed toward mice - they are too small and will cause musculoskeletal issues. Instead, use a larger wheel (8+ inches in diameter) or a disk spinner.

Mixed food and treats marketed toward mice - generally include food with dyes along with things like dried fruit. the dyes can be harmful and dried fruit is basically concentrated sugar. Instead, things like plain cheerios, unsalted black oil sunflower seeds, mealworms, and oats make excellent treats!

Critter trails and other small animal cages that are mostly made with solid plastic and tubes - these do not allow enough airflow and mice tend to pee a bit as they climb around on things. Unless you are cleaning your tubes and other solid areas out multiple times a week, you get dangerous ammonia buildup. On top of that, the bar spacing is wide and flexible enough that mice can squeeze through.

Exercise balls that you put your pet in to let them run around - these again have major ventilation issues and cause ammonia buildup. On top of that, mice use their whiskers and sense of smell much more than their eyesight to navigate, so these essential have them running around blind.

 

Perform at-home health checks as regularly as possible. This involves looking over the whole mouse; look in their eyes & ears, feel their body for lumps/scabs, and check there overall appearance, fur, spine, etc....

Healthy mice have:

•bright, clear, wide eyes
•soft, well kept, non-greasy fur
•upright, alert, clear ears
•long, prehensile tails with no kinks or trouble moving it
•no scabs, lumps, or injuries

•smooth slightly arched to flat back/spine that dosn't majorly bulge at the sholders

A mouse needs a vet visit if it has:

•dull, half-closed, or gunky eyes
•greasy fur, or bald patches
•ears pressed against its head
•swollen belly
•trouble pooping, or persistent diarrhoea
•kink in the tail, trouble moving its tail, or permanently carrying it over its body (wheel tail)
•blood in its pee, poop or genital area
•scabs, bald patches, severe injuries, or lumps
•prolapsed anus or vagina (this can be treatable at home)
•sudden weight gain or loss
•lethargic, suddenly sleeping more than usual
•wheezing, sneezing frequently, difficulty breathing
•running in circles (waltzing) or tilting its head (usually a sign of ear infection)

Signs of pain:

•half-closed eyes
•loss of appetite
•sudden weight loss
•ears pressed against its head
•lethargy

•Hunched over appearance or severely arched back/spine
•abnormal defensiveness (biting or squeaking when handled)