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Mice/Fat Pet Field Mouse



    As you can see our mouse Reggie is seen doing what he does best; putting on the ounces! Have read your response regarding the dietary switch to fruits and veggies. Which ones do you suggest?
     We have tried introducing a wheel into his environment but he chooses to ignore it.
     He has always enjoyed his food..but has never ate like this in the 4 years we have owned him. Could this be a sign of a harsh winter ahead?

ANSWER: Hi Greg,

Where did you get Reggie the field mouse? Did you hand raise him? You are so lucky :) they live so very much longer than fancy mice.

Another person who has a field mouse, which she hand raised with my help two years ago, says hers is getting quite fat as well. So it looks like there may be a tendency. Their little bodies are made to conserve as many calories in fat as possible; so I wonder why he remained trim for four years.

He should have had a wheel his whole life. Then he would still run in it now. But that's not fixable.

With fancy mice the answer is-- do nothing. Give him his seed mix, making sure to leave it until it is mostly gone rather than refilling often, so he doesn't just eat the tasty and fattening sunflower seeds (actually, you can take the sunflower seeds out), and no treats except vegetables.

If you want to try using a block or pellet instead of the seed mix, he may eat less because it doesn't taste as good. Then of course he has to have the variety of vegetables.

Did I really say a mouse should eat nothing but fruits and veggies? Sometimes I disagree with my answers from a few years earlier. A lot of fruit and vegetables will cause diarrhea, which can kill fast. I wish I could delete older, less well informed answers :(

In any case, I do not recommend putting a mouse on any kind of diet where he is ever hungry. I find that cruel. In talking to mouse breeders about certain types of mice which run to overweight, the consensus was that as long as their bellies aren't dragging on the ground and getting sores, a fat mouse had a body that wants to be fat.

A sign of a harsh winter ahead? Well, animals do have senses that we don't. It does seem, however, that this summer has been hot enough that I can't imagine his body could somehow be imagining cold. However, I am perfectly open to it if there is scientific reason to be. After all, this other guy is only two.

Squeaks n giggles,


---------- FOLLOW-UP ----------

QUESTION: Natasha:

     Reggie literally snuck in with our luggage when we moved 4 years ago.
    The species of wild mice in our current area are grey mice.Reggie is obviously not a grey. Reggies' predecessor was an alpha female (Willie). When we moved we had noticed that something was pilfering our poptarts! We set out a digicam on the kitchen counter and guess who showed up? By the time we captured him in a havahart it was too late in November. So he wound up w/ a nicely furnished 30  gal "mousie housie" . He does have a hand raised "neighbor". Jelly Bean... he is a Grey / Deer mouse mix and is an almost perfect 3 yr old wheel friendly mouse .

     Back to topic.... so maybe let him eat his fill sans sunflower seeds and remove the food dish when done? Could this and augmentation oh his diet w/ carrots or berries occasionally help? His belly is almost dragging.


Dear Greg,

The problem with removing his food dish is that mice are really supposed to be able to nibble all the time. It is a pretty extreme measure to the mouse's happiness.

Do you have a gram scale? Whatever you do from now on should be measured in his weight. Weigh him daily. Take his sunflower seeds out and reduce his extras to one vegetable a day-- carrot, salad greens, actually anything but tomatoes. But only one a day because it should only ba a small part of his diet. As long as he does not gain weight like this, he can stay this way.

If he is still gaining, then go to blocks or pellets. Again maybe one vegetable treat- and make sure he has plenty of things to do to make up for his boring food!  Only if he is still gaining weight that way would you want to actually limit his intake.

Best of luck to little fat Reggie.

Squeaks n giggles,



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I can answer questions about raising mice and caring for them as pets, with knowledge from my 38 years of having fancy mice as pets. I have NO MEDICAL TRAINING and you should take a sick mouse to the vet; but if you simply can't, I will try to help you. I LOVE PHOTOS!!! I ALSO LOVE UPDATES! Let me know how the little tyke is doing later on, for better or worse, especially orphans. It also helps me to help the next person. Please first search first: use 'Natasha Mice Mouse' with whatever else your question includes. Or check out these links: **** YOUR FIRST MOUSE (my video; rough draft): **** TEN VIDEOS ON RAISING ORPHANS: **** SEXING MICE: **** And some GREAT MOUSE INFO SITES:


I have had mice for 40 years (since I was 5!). I raised them when I was a child but now I keep all females, and never fewer than three so that if one dies the others are not devastated, because they have each other.

I run Rats and Mice are Awesome on Facebook. The official name is Rats are Awesome.

B.A., M.A., M.A. in Linguistics: Yale University and University of Connecticut

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