Mice Care Sheet

Mice are very small, quick, easily frightened and tend not to enjoy being handled. This means they may not be ideal for young children who enjoy handling pets.

But, they are fascinating to observe if given the right environment. As with all pets, it's important that an adult is responsible for making sure the mice receive the attention and care they need.

How long do mice live?

Mice live, on average, between one and a half to two and a half years old. They are fully grown at about three months old.

Do mice need company?

Yes. Mice need their own kind as company and love to groom and play with each other. Mice that are kept on their own can become very lonely and stressed and in extreme cases, may start to over-groom or bite themselves.

Here are a few ways you can make sure your mice get the company they need:

• females tend to get on very well together in pairs or groups

• a pair or small group of male mice may get on well if they are siblings but male mice from other family groups shouldn't be introduced

• a mixed pairing works very well, but it’s important to neuter the male to prevent the female getting pregnant. A neutered male can also live harmoniously with a group of females.

You should not mix mice with pet rats or other rodents, as they may be attacked and eaten.

When do mice sleep?

Mice are nocturnal which means that they sleep during the day and are most active between dusk until dawn.

What do I need to buy for my mice?

• Wire cage or tank

• Nest box

• Bedding

• Tunnels

• Food

• Earthenware food bowl

• Water bottle

• Shallow water bowl

• Ropes or an apple tree branch - for climbing

• Pet carrier – for any trips to the vet and for cleaning their home

As well as the above, your mice need a constant supply of water. You may also want to consider getting pet insurance.

Mice cages

The best home for your pet mice is a wire cage with a plastic tray floor. Tanks can be used, but it's important that they have ventilation holes in them (as some vivariums do) and a secure wire lid.

Avoid deep aquariums as they may not provide the right air flow. Wooden cages absorb urine (wee) and tend to become smelly.

Two mice need a cage size of at least 80cm x 50cm floor space, by 50cm tall.

Wire cages allow mice to climb - which they love - but they can squeeze through tiny gaps, so spaces between the bars should not be larger than six millimetres.

The cage should also contain a nest box filled with shredded tissue paper.

Where should I put their cage?

Make sure their home is:

• away from draughts, but in a well ventilated area

• away from direct sources of heat

• somewhere they can’t be harassed or attacked by other pets

How to clean a cage

• Wait until your mice are awake

• Remove 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 but, to make sure your mice are reassured by a familiar smell, keep a little of the old bedding (and if necessary, nesting material) to mix in with the new

• Using a pet-safe disinfectant, which you can buy in a pet shop, spray the cage

• Then wipe it all down and wash thoroughly with warm water

• Leave to air until completely dry

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

It’s important to keep the cage clean, but as mice rely on familiar smells to feel safe, make sure you put back some of the unsoiled used bedding when you do a ‘full’ clean (about a third of the bedding is ideal).

Bedding

Dust-extracted bedding or shredded paper are best. Avoid wood based bedding or scented bedding as these may affect a mouse’s delicate respiratory system.

Put bedding on the floor to absorb urine.

Enrichment

Climbing

Mice love anything that allows them to climb, so make sure they can do this.

If you use a tank, they will appreciate a fruit tree branch to climb on. Or, you could suspend lengths of rope as climbing apparatus.

Tunnelling

Your mice will also enjoy going through tunnels, such as cardboard or plastic tubes. Remember that by giving them these opportunities you're encouraging them to follow their natural behaviour and they'll love it.

You can also fill half a cardboard box with compost and allow your mice to enjoy some tunnelling sessions. Though be sure to keep an eye on them so they don't escape!

Activity feeding

Mice are known for scurrying around, looking for food. They naturally enjoy searching for food so you can help them display this behaviour by scatter feeding.

Randomly scatter their daily food around their cage and mix it up by hiding some in a paper bag. They'll love sniffing them out and it keeps the boredom at bay!

Gnawing

Gnawing is a natural behaviour that mice have. They chew on things to help keep their teeth healthy and to keep themselves entertained.

You can help them carry out this natural behaviour by providing things like:

cardboard

apple wood

seagrass

pumice stone

the shell of a coconut

What do mice eat?

A small amount of commercial mouse mix from a pet shop is a good basis for a mouse’s diet – but be careful not to let your pets become overweight.

Contrary to popular belief, mice do not need cheese or dairy in their diet.

Clean, fresh water should always be available from a shallow bowl.

How to keep mice healthy

Common illnesses

Mice are robust animals, but because of their short lifespan are susceptible to problems as they get older.

Mammary tumours

They are prone to mammary tumours and other tumours in places like behind their legs and on their neck. If you feel any lumps, get them checked out with your vet.

Respiratory problems

They may also suffer from respiratory (breathing) problems due to bacterial or viral infections.

If you are worried, seek veterinary advice quickly.

Self harming

If mice are lonely and stressed, they may start to self mutilate which means they will begin biting themselves. This can be quite serious and can lead to them really hurting themselves.

Skin disease

They can get mites and infections which can lead to very sore, itchy skin.

If you see your mouse itching a lot or with sore, red skin, speak to your vet. They will be able to look into whether it's an infection or a behaviour problem.

Should I allow my mice to mate?

Female mice reach sexual maturity at five weeks old.

A breeding pair will produce a litter every three to four weeks, with an average of eight to ten babies per litter.

And, shockingly, females can become pregnant within 24 hours of giving birth. It's strongly recommended not to breed mice as you will quickly become overrun!

Neutering

Mice need the company of their own kind and, to avoid unwanted babies, it is best to neuter single male mice so they can be introduced to females. 

If male siblings start fighting, speak with your vet about neutering as this may help.

How to handle your mice

• Start by placing your hand in their cage so they can sniff and get used to you, then gently stroke them

• Pick them up by forming a cup with both hands either side of their body and scoop them up gently

• Ensure they are always held close to a surface such as a table, your lap or their cage, as mice are fragile and they may get injured if they have a way to fall

• Give them a treat when you're holding them to reassure them that they get good things from being picked up