There are many facts of life, one of them so happens to be that male mice can be very smelly. This is not their fault, even non-territorial mice will smell. Whilst there is only one option to completely stop it, there are lots of ways you can minimise their smell.
What do they smell like? - it can be described as a damp, chlorinated smell of pungent ammonia. It is strong enough to smell up a room very quickly.
Typically the male scent decreases with age and a strong bond with his human friend. Young males will smell much worse, especially in the first 6 months. As your pet ages and the smell decreases you don't need to worry so much about odour control. Some males don't mark as much, especially if kept away from other rodents, and therefore the smell is manageable just with a clean out and wiping down plastic surfaces, but this is not the case for the majority of mice.
Please don't be put off of adopting a furry little boy, they are incredibly sweet, cuddly and good fun. Males typically bond better with their owner than females and are more likely to sit and cuddle. The smell in the majority of cases can be controlled if not completely managed so there is hope for controlling the odour.
But Males Stink!
You're here for one of two reasons.
1. You have just gotten male mice and they are stinking your room out!
2. You are thinking of getting a mouse and are now slightly panicked they will smell.
It is true that male mice do have a much stronger odour than females, but it doesn't make them any less of a great pet. Male mice produce a much stronger smell than females by nature and is their way of marking their territory every time they go to the toilet. The odour is caused by urine concentrated with hormones and such which helps them ward off the presence of other males and sets a boundary line for their territory. The mice themselves can't help this, even a very docile submissive male will still smell, often to a lesser degree, but his body will naturally be producing a more pungent odour.
Male mice should not be kept together under any circumstances. It is very, VERY rare you will find two males living together in reasonable harmony and those have been born together and grown up together without ever being apart. Not only will they be at risk from serious injury, starvation and even dehydration through the fighting and claiming of cage territory. Males kept together or in close proximity to one another will smell much worse as they will be constantly marking their territory to keep the other male out.
If you have one male then don't worry, you can jump to the next section. If you are thinking of getting male mice, please only select one. Males can live perfectly happily alone and it does help to control the smell. They are not nearly as sociable as females. A humans makes the best companion for a boy.
If you already have two then don't worry. Separate them into two cages and put them AT LEAST on the other side of the room to one another if not in separate rooms. You need to keep everything they own separate to prevent excessive marking. Wash hands thoroughly after handling, feeding or cleaning one male before touching the other to prevent the transmission of the scent. Believe it or not, mice have better eyesight than we give them credit for and sometimes even become jealous if they see you feeding/playing with another mouse which may cause them to mark even more.
Keeping the cage Clean.
Keeping on top of cleaning out their cages is essential for keeping healthy mice and keeping the smell down. Males can smell very quickly and it is important to not over clean them which can actually worsen their smell and increase their marking.
- Every day clean out the toilet corner and replace soiled shavings.
- Scatter a thin layer of fresh shavings over the top of the cage each day.
- Use odour neutralisers available from the pet shops often in granule form.
- Don't use scented bedding, pine or cedar. It is very bad for them and when mixed with male mouse urine can produce a pungent smell.
- Wipe down all of the bars on the inside and outside of the cage. Male mice have a habit of marking their bars so even a clean cage can smell like it hasn't been changed in a month.
- Keep your boy in a tank, these can really help to prevent odours from seeping out, although you still need a mesh secure lid so he can breathe.
- Avoid using plush things like nest beds, stuffed toys or cloth hammocks unless you plan to put hand wash them once per week as they will hold the smell in.
- Clean the mouse out at least once per week and spot clean every 1-2 days.
- Always air out the cage after it has been cleaned and before the bedding or mouse goes back in. Some plastics can hold in smells.
Sprinkling vanilla essence around the cage can really help neutralise male odours and it will not harm your pet. You can purchase vanilla essence from the baking section of any supermarket in a little bottle. A few drops should be good enough, although, be warned you need to change the areas you sprinkle every 1-2 days as vanilla smells can go off quickly producing a sickly smell and it will likely stain the shavings brown.
Please make sure you don't purchase essential oils, burning oils or anything that contains alcohol. Bakery liquid only.
You can also put natural vanilla essence drops into their water, 1-3 drops in a full size bottle is enough to help neutralise his smell naturally without causing him any harm. It's a good idea to alternate on days with plain water to give him a break. Vanilla essence is non-toxic to mice and will not discolour their urine.
Sometimes the diet of a mouse can increase his smell if he is being fed the wrong things. Mice need a good nutritious diet to stay healthy and help neutralise odour. Select foods that smell fresh and light and do not have a pungent, chemical or strong odour. These often contain unhealthy chemicals and additives. It is okay to give your friend fruit and vegetables in moderation but keep them plain like banana, apple and carrot and remove soiled food before it rots. Fatty foods are particularly bad for hormonal pets.
- Too many fresh fruits and vegetables e.g. sour apple or large amounts of anything, these can cause upset stomachs and can rot quickly making your pet sick and increase their bad male odour.
- Leaving food in the cage for too long, it should be changed and circulated daily to prevent food from going stale.
- Foods labelled for multiple animals. Specific mouse food is the best as it caters to exactly what a mouse needs. Many hamster mixed muesli foods are good as well, make sure you choose deluxe fresh ones. Multiple pet foods don't contain the right amount of nutrients or vitamins for all animals.
- Human foods. Not only are most toxic, they can increase the bad odour by too much fat, salt, etc which can make your pet unhealthy, give them a bad stomach or make them smelly.
- High fat foods can make your pet chubby as well as increase his stink.
Handling and exercise.
Males do not usually mark their territory on humans and are less likely to mark in an unknown space, e.g. your sofa. Letting them out to run about and explore is good for their health, their mental state and can help keep their cage from stinking up faster.
Spending lots of time with a lone boy and building a bond does actually decrease his natural smell as he does not feel threatened by other animals or that you are trying to wash away his scent. A peaceful adult male does not mark as much as an unhappy, lonely, adult male.
Candles, lamps, windows.
Burning certain candles in rooms can help neutralise or prevent odours. Candles made from beeswax substance or other natural properties can be extremely helpful and cleanse the air. You should avoid anything that masks the scent on a regular basis, and especially avoid anything that sprays into the air as this is detrimental to their lungs.
Rock salt lamps can also help to ionise the air reducing bad smells and generally cleansing it but these alone are not usually strong enough and only work when switched on.
Odour collectors, they are like filters that attract all the dirt in the air such as pollen, dust, mould spores and anything that causes bad odour. They are cheap and do not harm your health. These are great to be kept in the room with the mouse to help suck up his smells.
It may seem obvious, but try to open the window often. It will circulate the air in the room and make it smell better.
Leaving something Behind.
Leaving something behind with a bit of his odour on it can help to decrease the amount he will mark when he goes back into a fresh cage. Wooden toys cannot be washed or cleaned very thoroughly and can only be wiped down with a baby wipe or a damp cloth so they tend to hold in smells. Wooden chews are quite essential for mice to keep their teeth in good condition so don't deprive him.
If the wooden toy or chew or even his plastic nest house becomes foul, very stained or rots you should just replace it.
Contrary to popular belief, you should change his nesting material. He will be continuously weeing in it throughout the week and it will smell as well as irritate his skin in the long-run. If you use shredded paper you can leave a few small pieces scattered over the fresh stuff but always make sure it has been changed.
Neutering *Not Recommended*
The only way that really solves male mouse odour is to neuter them. Having them snipped prevents high levels of testosterone and the concentrated urine from smelling. However, neutering is very risky and dangerous and many vets are not able to perform it, some just plain won't.
Surgery is very risky for a mouse and many will die when unconscious. Neutering of males isn't unheard of but it is something that should be used only in an extreme last resort or if he is suffering health problems in that region.
Check for Infection.
Infections of the urinary tracts or intestines can make any mouse smell worse. UTI's are not as common in males as in females but they can happen. A UTI is caused by bacteria entering the urethra or just growing in the bladder and is often caused by dirty conditions. If he has an infection his urine will be discoloured, tinted with blood, he will be drinking excessively and may even squeak or cry when going to the toilet.
Injuries if they have been fighting with other males can lead to infections as well as wet tail which is caused from stress (although less common in mice than hamsters) if he has wet tail it will produce a very foul odour of diarrhoea, damp and other unpleasant things.
Nothing is making a difference. What should I do?
If absolutely nothing has made a difference and your mouse has a very foul or overpowering odour that is making you feel unwell you should take him into the vets to make sure there isn't something wrong. Hormone imbalances, infection, stress and other problems can cause the smell to become stronger. The vet can advise you on the best course of action whether it is treatment, a change of diet, or something else.
If the vet has checked him over and nothing is abnormal, you can try as many different nesting materials as you need and just keep trying. In the end something is bound to make a difference. Beware of some beddings that say "anti-odour" as many of them are heavily chemical treated and toxic, or they are large and chunky and the mouse can brush them aside to pee on the plastic which will defeat the whole point.
You may have to have an extractor fan in the room with the mouse to suck up some of the bad quality air and help keep it clean. Do not put the fan near the mouse. In some extremely severe cases there is nothing that will work or the smell worsens.
ThePetMaster (author) on July 23, 2015:
Thank you very much!
I'm glad this helped you :)
Anonymouse on June 21, 2015:
Very clear and detailed! I learned a lot from this!