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Mice/Male mice


QUESTION: I use to have a young male rex mouse and I noticed his cage always seemed a little greasy. I've had rats before and their cages never seemed that way or smelt as bad. What is it about mice that they have a stronger odour and their bodies make up a lot of grease sometimes? Is it just male mice who create it sort of like when a male rat creates 'buck grease' to attract females? It just seems so strange they create more than a rat and it seems to be in their cage too. I noticed I have to clean their cages more times a week than rat cage because it smells faster. It was just one mouse, so why does it create all that? defiantly not saying they're gross or 'stinky', just very curious.


Oh, you can say it!  Boy mice can be smelly!  What you are noticing/smelling is a kind of urine heavy with male hormones that mice (and rats) will dribble out across their territory to both mark what is theirs and to encourage females to go into estrus.  And yep, they can get it all over the sides of the cage, water bottle, hide, everywhere!  A little soap and water cleans it right off, though - I used to just use a wet wash cloth and wipe everything down each cage change.

This "marking" is part genetic.  Some males are more prone to abundant marking and smell very strongly, while others seem to never pee and smell nicer than the girls do!  It's also part territorial - if a female mouse is nearby (including wild mice), rival males, or even just if the cage smells "too clean," a mouse may be more inclined to make everything smell unmistakably like him.

You can help control this behavior, though, in two ways.  First, you can use a very absorbent bedding so the smell does not overwhelm the cage (having a well-ventilated enclosure is crucial in controlling the stinky).  I like Carefresh, as it almost ventilates itself, since it expands when wetted instead of compacting like some other options do.  You will find a bedding you find works best if you try a few, but you will probably still have to change the cage about twice a week, maybe even three if it is a small cage and gets strong too quickly.  The second thing is a neat trick that I have had a lot of success with - when you change his cage, take a handful of his old bedding and scatter it in with the new stuff.  This way his cage already smells like him when you put him back in it and he'll be (hopefully) less inclined to re-mark everything and undo all of your hard work!

I LOVE boy mice, but yes, they do come with a bit of a smell.  It's okay and totally natural.  Their fur should usually be clean unless their cage has become very nasty, but everything around them will need periodic wiping down to keep up to par with how you'd expect a female's cage to smell.

Hope I helped!  Let me know if you have any other questions!

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QUESTION: I thought that might be why. The boy I recently had made a lot of and after a cage clean I would leave a little of his smelly bedding behind to let him know it was still his territory. He didn't do so much as he got old though. We had wild mouse living in our house so no doubt he smelt them and decided to do what he did.

I was considering getting another pet mouse in the future. I don't know if I have ever owned a female though. I use to own a very large and unusual male mouse and his tail curled over his back into a ring. He got into a female cage by accident that belonged to my mother and when she had her babies he use to lie on them when she wasn't feeding them. It was certainly a shock because I heard the fathers eat babies but he was different from other mice and loved people.
Would you say males are more sociable and quiet than females are? I'd defiantly like to get a young one soon and tame it as much as I can. Though I know mice will always by shy no matter what. They still have so much wild instinct. Could you tell me the difference between boys and girls? I think all I know is females probably have more curiosity and don't create grease. And thank you for your response, I love to know as much about mice as I can!

I have found males to be more social with people, yes, but that doesn't mean girls aren't also very friendly.  Have you looked into buying a mouse from a breeder in your area?  A responsible breeder will let you see their setup, know the histories and pedigrees on their mice, have cool varieties (like rex, or satin, or long haired - most breeders specialize in one or two kinds), and be able to give their pups the hands-on attention that helps them grow into tamer, more affectionate pets.  There are less than excellent breeders out there, though, so always check first and ask as many questions as you can, but that may be a good option for you!

Female mice are very social, so a group of 2-3 will keep them more comfortable.  Males, on the other hand, should always live alone, which I think is part of why they are a little more loving with people.  Mice are individuals, though, and they all have different temperaments.  I have had female mice that loved people, females that hated other females, and males that preferred to hang out by themselves.  It just depends on the mouse.  This is another reason a good breeder might be a great choice for you - they will be able to tell you all about the personalities of their mice!

Because females live in groups, you won't have the sticky all over the cage, but you will still find yourself cleaning the enclosure 1-2 times a week.  Other than that, there isn't a whole lot of difference!

Do you have any other questions for me?  :)


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I can answer questions regarding mice as pets, mouse behavior, color and coat genetics, breeding techniques, and general health questions. I can help with caging and setup, nutrition, social issues, and what to do in most mouse emergencies (such as unplanned litters, injuries, fighting, etc.). I can also assist with questions pertaining to orphaned mouse pups, weaning litters, and questions of mating and birthing. I cannot answer questions about exotic or wild varieties of mice such as spiny or pygmy mice. *****FOR EMERGENCIES, anything requiring immediate medical intervention, PLEASE take your mouse to a professional veterinarian or wildlife rehabilitator who works with mice as soon as possible! IMPORTANT RESOURCES: Raising Orphaned Mice: Orphaned Mice Videos: Natasha's Your First Mouse: General Mouse Help: Mouse Info and Exotic Breeds:


I have enjoyed the companionship of mice nonstop since 2004, and spent a year caring for them in a lab where I learned a great deal about their breeding, social needs, and health. I spent a few years breeding them, specifically working with albinos, marked mice, angora mice, and satins. My education never stopped - I am learning something new every day from current and well-established research thanks to the wonderful folks at the Jackson Laboratory, as well as from my wonderful mousey friends online. I also love learning from my terrific questioners here on AllExperts - you folks keep my passion for these amazing animals alive and well!

East Coast Mouse Association - expired, American Fancy Rat and Mouse Association - expired

Partial University for a B.S. in Microbiology, Partial University for a 2-year degree in Veterinary Technology (RVT cert), C.E. classes in pathogens, aseptic technique, genetics, and applications

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