About a month ago, I tried my first stab at breeding mice. In the end, it was heartbreaking (don't ask me how dying babies makes me cry, but watching older ones be constricted puts a proud smirk on my face).

Maybe it was the bedding, maybe the enclosure wasn't warm enough, maybe they were bred too young, or perhaps the vicious RI the female had is what did them in. I'm pretty sure it was the RI. But HOW did the RI happen?

I quickly skimmed the current threads on here, and got a ton of ideas. I would just like to know what I can do with what I have.

- 1.2 mice. Male appears to be younger than the females, so would NOW be the right time to separate them, let them age a few weeks, and then start the breeding?
- Aspen. Should I use only a little aspen like some people have said, chuck in some toilet paper tubes, and use newspaper as liner? I currently use newspaper as liner, ALL aspen, and a couple tubes, but they just burrow underneath the layers of paper. (In my last attempt, a friend gave me "hamster fluff". Is that a big no-no?)
- Lab block diet, "hamster/gerbil seed mix", occasional bread. How can I better their diet?
- 75 watt blue heating bulb. Do the babies need a lamp for added warmth if the house is under 70 degrees Fahrenheit? Even though the mothers will typically keep them warm?

I think the biggest mistake I made was having only one female, and breeding too soon. I didn't take into account that she might get sick, and there wouldn't be another female to care for her young.


What can I do better this time to ensure their chances of survival, both parents and babies alike?

Thank you!
PS: Sorry for such a loooooong post. Please bear with me.