# Help!! Male mouse attacking new female + Breeding question



## LeodegarioAdolfo

So I have two little mice, Milk (female) and Muffin (male). I purchased them from a local pet store and they've gotten along great, they love to groom and cuddle on top of each other when they sleep. It's about to be one month since l got them and have grown in size considerably. Now they get along just fine, but my main issue is that they haven't mated! Not even once! Muffin has tried several times to mount Milk but she pushes him and runs away. They clearly like each other but she won't let him mount him, this clearly saddens me as I do want to have babies  Any ideas as to why this can be?

Also in another issue, I recently purchased another youngster female (same pet store), named Burger; trouble began soon as I put her on the cage. Whereas Milk doesn't even seem to notice her, Muffin began chasing her and being rather aggressive with her, to the point that Burger won't even move from the little hideout she made under the running wheel  Why is this behavior occurring as I've read that males won't fight with other females? Or is it because Burger's a youngster and the other two are older?

Help please!!!


----------



## Psy

First things first, males absolutely can bully females, put that out of your head right away. Additionally some females won't approve certain males, and theres little if anything you can do about that.

Now that that's addressed we can begin.

The first concern that comes to mind is gender verification, I don't personally know your skill level with mice or breeding, so don't be too put off by derp questions. Are you sure all mice are the gender you believe them to be? To me it sounds a bit like female dominance behavior. A clear picture of 'his' and 'her' genitals should resolve that question. No shame in a misidentification afterall, it quite literally happens all the time.

For the second female who is hiding in a nest under the wheel, are you sure she isn't already pregnant? they tend to begin nesting when they realize they are, which is what the one under the wheel sounds like.

How big is their breeding space?
How did you introduce the initial 2?
How did you introduce the additional female?


----------



## Psy

Having spotted your other post, I can assure you that your cage is in fact big enough, but heed the advise of that other thread, those plastic tube add on cages... **shudder**.

If all other concerns outlined above (females are all females, males are all males, and they don't have an actual aversion to one another, appropriate ages, etc), then my primary thought on the matter would be too much or too complicated of space. I find that a less overly stimulating environment for breeding in helps a great deal.

When I mate my mice, each male has his own breeding tank. The ones I use can be found here at the bottom of this post, you do not need to plumb your rack or buy any other component of the breeding cages save for a water bottle at the least as they are designed to fit the cages due to the odd angle the cages provide. the benefit of these cages being they are smaller, but not overly so, and provide feeding and watering from above to prevent things at ground level getting in the way. I provide no distractions in these cages, no toys, no hide, no bowls or tubes. There is nowhere for a female (or male) to feel cornered within or hide away.

You can either leave them to mate for a week or 2 (I go with 2 for good measure), or you can just leave them until they seem "cuddly" with one another, as they often do this after mating. some here believe that the squeaking stops when the deed is done. 

Rodent Breeding Cages: http://www.reptilebasics.com/rodent-caging/


----------



## LeodegarioAdolfo

UPDATE: OMG OMG OMG Milk and Muffin (both) badly injured little Burger, I had to put her out of her misery. There was blood all over the bedding paper! I'm just so shaken, why would they do that?! :-| :shock: :-o :-| just...why????


----------



## Lilly

I'm sorry that this happened. A few things for the future.

* Its generally a bad idea to introduce a new mouse without QT in case of any illness
* When a doe is pregnant she often can act a lot more aggressive to new comers, since she has been in with a male that is a big possibility 
* A young mouse should not just be put in with a male as she is not old enough to breed. Usually should wait until 8-10 weeks for faster to mature lines before pairing because when they are still growing they cannot produce the milk volume that a mature doe can so are more prone to complications.

I would also be thinking that there was the potential that Burger was in fact male. Although males can bully females, extremely aggressive behaviour like that would make me think that another buck was put in.


----------



## Psy

Exactly my initial concern, gender identification. Not gonna lie, kicking myself for not insisting a bit more on those pics...

I know this is a bit late, but in case it comes up again, are you familiar with humane dispatching methods? It's never easy, but the knowledge can certainly help with the understanding that you did everything you could to minimize suffering.


----------



## littlepiggydog

Psy said:


> Exactly my initial concern, gender identification. Not gonna lie, kicking myself for not insisting a bit more on those pics...
> 
> I know this is a bit late, but in case it comes up again, are you familiar with humane dispatching methods? It's never easy, but the knowledge can certainly help with the understanding that you did everything you could to minimize suffering.


A c02 chamber would be my preferred way of euthanasia, very simple to make and also humane. There are debates about whether it's as humane as Cervical dislocation but i couldnt bring myself to do that


----------



## Psy

I've had to do it twice in instances of pain due to injury, its about as far from easy as you can get, but is necessary at times. I agree and do use a chamber myself for typical situations. but in a situation like this, provided I'm understanding the particulars, in the interest of limiting suffering, I would have absolutely gone with cervical dislocation. but that is largely to do with the fact that like many, I would have had to go collect some dry ice (the vinegar method hates me), which would have prolonged suffering.


----------



## littlepiggydog

You can also use a co2 bike pump. You put a canister of co2 into a pump, attach the pump nozzle to a plastic tub through a hole with another hole to let the oxygen out and it will work just as well. Well so ive heard and seen ive never done it myself


----------



## Psy

I have seen videos of this yes, but never known anyone who's used it. my concern would be, with the dry ice method I have a very clear understanding of the amount in the air of my chamber. where as with the co2 canister i would assume i wouldn't see anything. beyond that i have no concerns, it sounds like a good method. good of course being subjective...


----------



## Lilly

Psy said:


> I have seen videos of this yes, but never known anyone who's used it. my concern would be, with the dry ice method I have a very clear understanding of the amount in the air of my chamber. where as with the co2 canister i would assume i wouldn't see anything. beyond that i have no concerns, it sounds like a good method. good of course being subjective...


Not that we are really supposed to be discussing methods here as far as I am aware but it is advisable to get a flow meter for that


----------



## Psy

I didn't mean to cross any lines, just looking out for the little ones. I will step back though


----------



## Zamwyn

There's a specific culling board one can request access to if interested, having made at least 50 posts is the requirement.


----------

