Can I add another mouse?

[Auskan]

Well, all I know is that I've been keeping and breeding mice for years and I've never had a male that it wasn't really obvious he was a male.

[marisa]

It's not that its not obvious, its that males CAN and WILL pull their testicals up at times. Not an arguement point, not a big deal. It doesn't mean they aren't obvious males. It just means that they can "hide" their testicles.

But it doesn't matter, because looking for testicles is not the best way to sex anyways and cannot be used on the youngest of mice. Look at the size of space between the anus and genitals is the most simple easy way which allows you to sex at a far younger age then just waiting to look for testicles.

Not a big deal. No one was argueing with you.

Marisa

[Auskan]

No, no, I never felt anyone was arguing with me - I have just never heard of them doing that, and I have been keeping mice for a long time (though only recently as a food source - prior to that it was a "hobby" and I supplied fancy mice to a local pet store). Marisa, any idea why they pull their testicles up? There must be a reason.

[Lisa]

I've found it's the way you hold them... you have to stand them up so they're feet are low and their back is vertical.
if you have the rump up high the testicles sink in.

I think they may also "suck them up" to protect them, it's not uncommon for rival males to do damage to the others reproductive organs.