Took in 3 females, think theyre all preggo-HELP

So 11 Days ago, I took in 3 females. All seemed fine, they were healthy, young (10 weeks old) girls. Now Im very concerned that I may have taken in pregnant females. One of my males did get out a few days ago, and I found him climbing up their cage, but I highly doubt he impregnated all 3, through a wire cage, within about 5 minutes. Ive seen the dance that mice do, and it seems unlikely for one mouse to get pregnant through a cage (though I know its happened), it seems nearly impossible for it to happen with 3. Not to mention that was just a few days ago, and these girls look about ready to pop. I had taken them in with the intention of them being pet-only, and am really unprepared for this. Ive done a ton of research, but wasnt planning on breeding for atleast a few more months (and wasnt planning on breeding these girls, period). I took some pics of their bellies, hoping to get confirmation on my suspicions. If they are pregnant, I need to start looking for homes for babies. Since I hadnt planned on breeding until I move in June (at the -earliest-), I havent even started any kind of waiting list or getting contacts for possible homes. Not to mention since the litters would be a complete mystery, I wouldnt feel okay starting my mousery out on unplanned, unknown lines. Should I find completely random homes (like on craigslist) or adopt them out through the mousery with "pet only non-breeding" contracts? I really dont know what to do here... But, hopefully Im just losing my mind and they arent preggo. So, lets go to the judges...
10 days ago (when I got them)






What they looked like last night:

This is what I'd call "ready to pop." (an example of a past momma)


While yours are definitely not to this stage yet, the rounded abdomens I would put at mid/final week of pregnancy. If it's their first litters, they might be caring less and therefore look smaller pre-littering, so it's really kinda guess work for you. I don't know if you plan on littering them together or separate, but I'd start setting up tanks if it's the latter.

If this situation happened to me, I would first see what came out variety wise. I don't know if you planned on starting with established lines, but since you got them in a pet store in the first place, I'm taking a guess that there aren't any real breeders around you? You might get a really interesting variety out of the mix, and as long as you're picking healthy mice and do some selective breeding, I'd say go ahead. If anything, you could consider it a test run before you spend money on expensive, established mice.

Secondly, since it sounds like re-homing is going to be a challenge for you, I would strongly consider culling a portion of the offspring. I don't know your feelings on it, just keep it in mind that while hard to make the decision, it does result in less mice, and the ones you keep are healthier because their is less competition among their litter mates, as well as financially it costs less.

Since these aren't anything special (breeding wise), I think it'd be silly to do the "no breeding contracts." There isn't any real way to know if re-homed mice are being bred, the things you'd need to do to have it legally binding seem waaaay more effort then it's worth, and you'd need to pay money for genetic tests to actually prove if someone bred from them.

You could try to advertise on hoobly.com as well as craigslist when the time comes, but just my experience, in the 7 months I've been breeding and advertising my extras, I have sold 2 mice as pets, 1 breeding feeder, several dozen as f/t, and donated another several dozen to a raptor rehab center. Depending on where you live will depend on the interest in buying mice as pets. Other members might have had better luck with this, but this is just my personal experience.

I have great luck with CL, personally. In the last month, I've re-homed nine mice, not to mention those sold as feeders. I would still strongly urge you to consider culling at least the male pups, until you get a litter of 6 or 8.

Also, those mice could be close to birthing time, but I doubt it. You've got at least a week, probably closer to ten days before those are ready. They were probably pregnant when you got them, but only just.

I'm also pretty heartily against contracts. They don't really help anything, that I've seen, and I'd rather an adopter feel like they can be honest with me that they're looking for feeder breeding mice, or they're looking to produce a single litter so they can teach their children about biology, or whatever it is that they're after. I can provide mice more appropriate for those aims, and if they don't get them from me, they'll still get them.

Oh wow! I thought contracts were kind of the norm. I guess the rat world is a lot different from the mouse world. I have a friend that runs a rattery, and she was pretty much hung on a cross for even owning a pet store rat, and would have been seriously black listed for breeding them. I was trying to follow similar ethics. I was really freaking out about these girls possibly being preggo, thinking no one would work with me. Im glad thats not the case. Ive seen that mice breeders are a lot more welcoming of new comers than rat breeders. Ive still been coming to terms with culling. I understand that its for the best of the litter (as well as for the space in my mousery). I think I wont ever be mentally prepared for culling until I actully do it. Any helpful hints and tips for newbies with culling? Ive researched all I can, for methods and stuff.
And the big question: so the general consensus is that, yes, these girls are pregnant? Also, would you guys recommend letting them have their litters together? They are (supposedly) litter mates, and are very bonded, but im curious to see which mouse produces what offspring, since I have no idea what the father was...

lol, different is an understatement! What I did to prepare myself for culling was to bring over a friend who supported why I needed to. Having her there meant I couldn't chicken out, and she would reassure me that I was doing everything right. Idk which method you are contemplating using, but you might want to do a test run on your freezer or practice throwing some grapes at the floor.

A lot of people are at rodent fest this weekend, so you'll probably get a wider range of opinions when everyone gets back. I would personally litter these separate so that you can keep a record of who comes from what. In the off chance that you were to end up with all agouti mice (just a scenario), if you kept everyone separate you'd know which of the offspring carry chinchilla vs. pied. Plus, if there are different colors, it'll help you ID what the mom's carry. For example, if any babies come out with pink eyes, you'll know the mothers either carry the genes for pink eyes or albinism (won't be able to tell until they fur).

If I were you, I'd maybe keep a male or two from the chinchilla mouse. While not impossible to find, these are more uncommon then the pied or black mouse. Keeping a male means you could breed him back to his mother or sisters to create more. idk what the rat world teaches you, but inbreeding/linebreeding is generally considered a legit practice with mice. Some people will give you recommendations how far apart on the tree to breed, just know that there has to be some inbreeding somewhere if you want to maintain mice of a particular variety. Especially when you're gene pool is limited by what's in your area.

Jen, I am developing a mathematical theorem to determine how many babies a pregnant mouse will have given her starting weight and her ending weight. I thus know what a pregnancy weight gain curve looks like. If you have a gram scale and can weigh each of your does daily around the same time and send me their weights at ann.marlowe@verizon.net, I should be able to tell you within 5-6 days who is pregnant and who is not, even without their beginning weights. There is a nice form to keep track of their weights at:
http://mrsbeachsbrindleempire.tripod.com/litter-theorem.html

And if you enjoyed doing this, maybe when you start to breed on purpose you could weigh your does for data for my theorem.

Frizzle, you displayed my thoughts exactly with separating them. I have a black tan male that I had thought about breeding with the chinchilla, which from my understanding of the genetics, should produce foxes, yes? But I wasnt sure if she was chinchilla or silver agouti, (was pretty sure she was chinchilla, but Im still learning), so I hadnt planned on going down that road. She was actually the one that made me take a second look at the girls in the tank, the pied and chocolate one (she looks darker on camera) seemed like nothing special to me.
And you are correct, I dont have any breeders remotely close to me (a major reason I started looking in to breeding). I was planning, when the time came, to drive to southern California (about a 9 hour drive for me), as there are a few breeders Ive talked with down there. My other option is north, going in to Oregon, where the breeders are about an equal distance. I was wanting to wait until after summer, however, due to the heat mixed with a long drive. I imagine thatd be rather unpleasant being covered in fur and stuck in a small travel cage.
As far as culling, Im not sure what method Im planning on using either... Lol. Id imagine, if given the choice, Id rather be shot in the head and killed immediately than freeze to death, but Im not sure I have the guts to kill babies with my bare hands. Ive heard of people using co2 chambers, but getting the materials for that seems like a challenge. How would I go about doing a test run on my freezer? Also, how long would it take babies to die in a freezer (roughly). If its a long process, Im pretty sure I would try to rescue them, which Im sure would leave them brain damaged or something, and suffering more.
As far as the inbreeding, I know thats common. It still strikes me as odd, but I know its widely accepted. lol.

Mrs.Beach, I would LOVE to help with that. A big part of my interest in breeding mice was so I could study the genetics/health/etc. I love genetics, but dislike most other sciences, so choosing that as a career path was out of the question. So I use it as a hobby instead. I dont have a scale yet, but was planning on getting one before breeding (Ive seen other peoples posts where you've asked for weights). It will probably be another week before I can get one, and it might be too late (With these girls) by then. But I will definitely send you weights with my planned litters!

If the pinkies aren't solid in three minutes, your freezer isn't fast enough. Someone elsewhere suggested trying a fresh raspberry. CO2 isn't effective for pinkies or really most mice under two weeks, who are designed to handle the low-oxygen environment of the nest. And freezing of course isn't at all humane for animals over 3 days, which leaves you a gap where the only humane methods are throwing/thumping/cervical dislocation (depending on size and what works for you).

Just tossing this out there, but my buck and doe got their paws on cat kibbles and both of them are close to resembling your chinchilla lady. I'm quite shocked.

Yes, culling is difficult. It's taken me a month and a half to finally put the buck and doe together making peace with what I have to do to the boys (or rather I hope I select boys!). I was JUST thinking my freezer hardly seems cold enough so I'll give the raspberry test a go.

(and yes the rat breeding world is insane - I'd rather breed rats but much prefer the company of mouse breeders!)

I think this was a False alarm. They havent gained much more weight over the past few days, I think it might just be the significant increase in nutritional quality of their food, mixed with their growing bodies.

Oh good. I wondered, as my doe started looking a lot like that a few weeks ago and it was just a combination of her growing up plus getting better food. Oddly enough she's lost most of that weight but when the buck gets a roll like that it's easy to breathe easier!

Jencandy, I'm glad you'd like to collect data for Mrs. Beach's Litter Theorem. The Triton T2 is the scale I use. Inexpensive and available from Amazon. I just saw a new one there for $13.

Yeah, its just odd that all my mice are on my food mix, and theyre the only ones that exploded.

I will probably buy that one then, as Im sure using the same model scale will help increase accuracy. Should I weigh them starting the first day they are paired or? Im going to buy the scale on friday, and will possibly be pairing one or two next week (after I can be absolutely certain these girls are not preggo)

I started weighing Tully the day prior to being put in with the buck. Also, try for the same time of day. It's funny how that can make a whole gram of a difference! (it's been a week, she's only gained two grams)

And I hear ya. My older ladies are on the same food. But then again they're used to it and aren't growing. I guess they saw the goodies and gorged?

I guess so. Lol. I keep looking at them and thinking "maybe they are....", but its pretty much settled with me that they arent. Im glad, because who knows what would have come out of those litters. But Im sad because... Well, who knows what would have come out of those litters! Now I just kind of have mice fever and want litters galore, but Im controlling thay temptation-I dont want any babies before I move at the end of this month, and I dont want a preggo mama getting stressed over the move. I know waiting is the smart move, but its so hard!

Mrs beach, does that scale do well with moving objects? Lol I realized I have a scale up to 550g, but my mice wont sit still so it shows their weight anywhere from 7g to a few hundred, depending on how theyre hopping around. Will this scale help with that issue or should I just stick with the one I have? I suppose I could zero it out with a small container and put them in that...

I bought a tiny scare that came with a weighing container. Lol. Have not used it yet but will. ,

I'd say yeah, zero a small container that keeps them fairly centralized because as they move from the middle it could change how they get weighed, like if you only put your toes on a scale.