Fat mouse?

[Zoe]

I have a colony of four mice, and one of the females is VERY fat. She has bulges under her chin and arms... in fact she looks more like a gerbil or hamster than a mouse!
The others are not fat. They eat assorted grains (corn, barley, oats and a molasses mix), and fruits and vegetables. Is she sick? Pregnant? Or just a big fatso?

Thanks
Zoe

[vanderkm]

Some genetic lines of mice are prone to obesity - especially the red color coat (sort of orangish red color). The genetic tendency may occur in other colors as well, so that is a good possiblity. We did not have good reproductive performance in these lines (despite the fact that the reds were pretty) and they had very aggressive tendencies.

There are metabolic diseases that can produce obesity (hypothyroid, diabetes, pituitary tumors) and mammary gland tumors are very common in some mice - but these are usually very visible as discrete lumps - but be aware that mammary tissue in mice extends from the chin to the tail and up over the shoulders and back - so if these are actual lumps rather than just bulging fat, it is likely mammary tumors.

Pregnant mice have clearly bulging bellies and not much fat elsewhere. Nipples also become quite prominant by the time they are advanced and near having pups.

The diet that is heavy on highly metabolizable carbs may not be as balanced as you might like for optimal production, but mice are really pretty resiliant - they do well almost regardless of what they are fed.

mary v.

[GotBalls?]

I have a brindle mouse who is obese as well, and I have heard that that color strian is prone to it. Her sister who is I think a fawn is chubby but about half the size of her sumo mouse sister LOL.

I work at a lab that has mice all of the same strain, usually 4 mice per cage and sometimes there is one mouse that is a couple of time larger and fatter than her sisters, and some times they all end up fat, depending on the age and strain. They are all fed ONLY lab blocks, although the cages aren't huge so lack of exercise could be part of the problem. The males and females that are used in the breeding program and get a high fat diet ( it's meant just for the nursing females but since the males are in the cage with them they get it too) end up what I would consider morbidly obese, which my little mouse may end up being since she is only about 10 months old at the moment. Mine only get lab blocks and some seeds and grains on occasion, and little bits of food that I am eating ( the odd nut or piece of fruit/veggie etc)

Unfortunately I guess mice are just like people.. some can eat all day and never gain a lb...others are air ferns..

Nicole

[Zoe]

Thanks for the tips! I will try to adjust the diet slightly, and offer more fruits/veggies and less grains.
The mouse in question is brown, the "wild" colour. Brindle? I don't think they are tumors. She just has about 5 chins...
If they are indeed tumors, is it unsafe to feed her to a snake?

Zoe

[Linds]

As long as tumours aren't caused by an envionmental toxic, it is perfectly safe to feed them to snakes. In the wild, the sick are preyed on first. Diseases and disorders are host-specific, so your reptile cannot catch it, however if caused by toxins, then you don't want your snake ingesting any as well.

[Zoe]

Thanks Linds!
How would I know if they are caused by toxins, if they are indeed tumors? Would it be safe to assume that all my mice would be affected?

Zoe

[Linds]

Short of having a chem analysis lab...lol... you can only try and guess if it has come from toxins through elimination and speculation. You have to carefully exmine the environment around them, and then think about if there was anything possible that they could've been exposed to, or if their food/water could've been contaminated.

[GotBalls?]

Sounds like your mouse is an Agouti. The Agouti's we have at the lab often get extremely fat, but it is usually only in the stomach. But they are a different strain than your average mouse.

The mice I have are fancy mice, I have them as pets...a brindle mouse is the same color as a brindle dog... very neat..

here she is as a baby...before she got fat hehe