How To Care For Your Pet Mice :)

The basics

Pet mice are scientifically known as 'Mus Musculus Domesticus' they are descendants of the old house mouse we find in the wild usually in garages and sheds or basements and rooms that are unused often damaged this includes barns.

Mice kept and bred as pets are known around the world as Fancy Mice. In the pet store you will often find tanks of mice from groups of two to ten sometimes more. They will be pre-sexed and a good pet shop will sex them properly, find one you know and trust that has been around for a good long time this store will be a much better choice to the new one that opened downtown, you can trust it. Make sure the tanks are separated males from females, both genders will often be brothers and sisters so a breeding pair will be better bought one from one shop and the other from a different one so they are not related as inbreeding can cause shorter life spans, longer harder pregnancy and complications are more likely to occur.

Choosing your mouse: You want to pick a pair of females, it is better to keep them in a trio as in the future one of them may die and leave the other one alone so a trio will keep a pair left so they will not be alone. Females can live together 98% of the time with no problems at all, some may have the odd scuffle but usually nothing that will cause any problems. Male mice must live alone, if they get on fine in the pet shop there is no guarantee they will be fine at home as they will move into a new house a new environment and the more dominant male will automatically try to rule the cage often leaving the other without food or water, isolated in a part of the cage such as a corner or a hammock, they will also fight and once they draw blood that is the point of no return they must be separated immediately because the dominant male will kill the submissive one and could be severely injured himself. I recommend a single male or a group of females they will get on so much better and have happier lives. I do have to warn you that male mice mark their territory with a strong odour urine and jelly which smells like ammonia and sometimes a bit eggy too.

Pick mice or a mouse that is bright, alert, with clear eyes no discharge from any area. Do not pick one that is unhealthy, shaking, quiet hiding in a corner alone this mouse will almost certainly be sick it could even die or end up with problems when it does recover. Do not choose a runt unless it seems very healthy and bright. You want some nice strong looking active mice this can be hard to determine if they lift the house or wake them up as they will be docile. Pick ones with a shiny clean full coat, no patches that appears happy.

Housing for you new bundle of fluffy joy:

I highly recommend a cage, a wired close bar cage or a hamster cage. These are most suitable for you pet as they will air the cage out well, provide essential climbing space females in particular like to have it also promotes exercise and entertainment. Don't get one that has a wire spaced wheel or ladders, plastic only as small mouse tails and fingers can be trapped, even necks can be trapped and broken very easily in these things. Wire cage with plastic house, wheel and ladders are safest and easiest to clean. Males will mark the bars so you need to wipe every bar it makes the job harder for you to clean. Tanks are not healthy for you animals, although easy to clean they have no climbing space, are known to build up ammonia and other fumes which can poison your animals and make them very sick, you will need to buy wheels on stands and floor toys too which is a big pain for you you will also need a very deep bed of non dusty wood shavings for them to dig through. Double floored is best make sure you buy toys you will often be able to buy a starter kit including cage, mice, feed, shavings and the basic essentials. You should have wooden toys for them to cut their teeth down on as their teeth never stop growing. Feed should be supreme science selective NOT hamster food as this can be too rich and not easy to come across, rodent mix is also fine as long as it is marked safe for mice and make sure it is one you can get easy. They can have a small amount of boiled rice, sunflower seeds (which they love) and mouse treats from the pet shop. Fresh water must be available daily also check the bottle as it can break or block leaving your mice dehydrates and dehydrated mice can die within 48 hours.


The easiest way to catch your mouse is to gently grip by the root of the tail not the tip as this can hurt them, if they squeal don't let go lift them quickly and place them on the palm of your hand and hold the tail until they settle. Don't attempt to play or handle your mice for two days at least after you have them as this will break the trust and make them hard to manage and fear you for a long time. Tame mice can be picked up very carefully as a hamster but be careful not to grip or squeeze as this can kill them and they can take days to suffer from it. Once fully tamed they will jump into your hand or ask to be picked up.


Never use aspen or cedar any soft woods are a bad idea because they are full of oils and chemicals which can poison and kill your mice as well as cause URI (upper respiratory infection) which can also be fatal.

Wood shavings are perfectly safe for your pets provided they are large non dusty ones I personally use horse wood shavings as they make no dust and carry no parasites. Old, dirty or dusty ones can breed bacteria. Carefresh is a good bedding to use but only to mix with wood shavings it is used to absorb urine and odour and is no use used on its own as it will be knocked out the way and the mice will toilet on the plastic. Nice. Don't use any wool style bedding as they may try to eat this and it can cause blockages, swelling, poisoning, constipation and problems with their digestion. Although they are traditionally used with hamsters etc they are not very safe. Use a good non dusty hay packages correctly as this is great for digestion, teeth and natural they also love it and it keeps them very warm. I use herbage timothy hay and my five love it.

Cage Cleaning: 

Never bathe your mice they keep themselves well groomed the moisture can cause arthritis, stress and other problems for your mouse. 

Clean the cage twice a week (sometimes more frequently for males) with a specialised cage cleaner not bleach or detergents one that is labelled safe for mice, usually if safe for hamster cages it is ok for mice. Make sure you follow instructions and clean away thorougly with hot water. Dry and fill with fresh shavings. Leaving a males nest and one marked toy (As long as they are fairly clean) can help stop him from marking again keeping the smell down. Females are ok for a full cage change. Wooden toys are harder to clean and may be wiped down with a baby wipe or a damp tissue no detergents as they can poison your mouse.

Health Problems & Pregnancy

URI (Upper Respiratory Infection): Often caused by dusty, dirty damp conditions in cages and tanks. This can be fatal to your animals. Symptoms include laboured breathing, runny nose and eyes, shaking, abnormally docile, loss of appetite, dehydration. If you suspect your animal may be suffering take it to the emergency vets immediately. This does not cost much and will save your mouse' life. 

Tumors: Common in older mice, some are just fatty benign lumps of tissue that sometimes can't be removed and will do no harm to your mouse. Some are cancerous and will swell and there is not much you can do because it is very hard to operate successfully on mice even by the best of vets as they can overdose, die from shock, infection etc very easily. Get any lumps checked, most will appear on the sides of the mouse. 

Discharge from eye: This could come in white, clear, yellow or red. The most common cause of this watery eye is caused by an allergy to dust, it could be anything and it can take days for an allergy to pop up. If a mouse has sensitive skin and baldness it could have severe allergies and use only the most gentle of products and feed. Stress and anxiety are other causes this can happen easily often when they are on their way home from the pet shop and sudden change in environment. Something in the eye is another common problem and will usually resolve itself again, wipe away the discharge and attempt to bathe the eye in warm water only if the mouse wont let you they will resolve it themselves quickly. Infection and diseases are usually from excessive pussing, swelling, inability to open the eye and heavy amounts of watery discharge often from both eyes. You should get them checked as white spots on the eyeball can be a sign of the mouse going blind.


Mice are pregnant for three weeks, they show just over a week before the birth some show enormously some don't show much at all. Often they will look like the have swallowed a golf ball and their behaviour will drastically change, nest building is common in all mice but more excessive in pregnant females. Their teats will swell and they will be eating more and sleeping more. After mating for around 16 hours there will be a plug inside the female stopping other males from mating with her you may be able to see this inside the mouse or in the cage when it comes out. Litters can be from 4-18 usually being around 10 and mice become sexually active at 4 weeks of age when the males MUST be removed as they may try to impregnate their sisters or mother. Mice pregnant under the age of 12 weeks may die, eat their litters, suffer complications, short life span for the mother and babies. Four months is the ideal breeding time. A mouse must not have more than three litters in her life, the first between 4-5 months and the last at around 7 months. 8 months is too old for a female to breed and may cause problems even death with her she is still capable but if she has never had a litter before she may die from stress. Females must have a break after having the first litter of at least four weeks after the litter has left her at five weeks of age because she can die or have complications. Males must be removed after mating and no males should be around the smell of another male, stress etc can cause the female to abort her babies and absorb their fetus' or she may birth still borns or just eat her babies this is rare but does happen. Males will try almost instantly after the birth to mount the mother (the father of course) and get her pregnant again so make sure he is out of the picture. Do not touch the nest before or after the babies, make sure you cover your scent and do not touch the babies for at least four days after birth. Too much of yours or another scent can cause the lady to eat her babies or just kill them so be careful. Baby mice mature at different rates so don't be surprised if one is super hairy and another just has peach fuzz.

Wet Tail: 

Not too common in mice but again caused by dirty conditions. If no bowl of water is present and the area above and below the tail is continually wet even in clean cages this is a sign of wet tail go to the vets straight away. 

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