Newer rats (2) had 32 babies!

Question
HISTORY - Well, about 15 days ago I purchased 2 female rats from a local pet store. The worker said they were both "young" and neither had had babies before (we didn't want one's that had been used for breeding). They are both very calm, enjoyable rats. We handle them daily, and they seem to be fond of us. The past couple days however, they have been nippy and kind of "coward" when we reach in, it takes them a second to calm. My only answer, although not sure of it, was that they were possibly pregnant, because their bellies seemed to be bulging quickly. However, they BOTH delivered babies yesterday! Here's my situation:

Yesterday: Jessica had 19 pups at 9:30-10 am. She was ignoring them, so at 11:30 we put her in a 5 1/2 gal cage (instead of the one they share - 20 gal long) to try to get her to sit on the pups, as I had read to do. However she still continued to ignore them. I went to the pet store around 12:30. She apologized stating her daughter had an "accident" and one of her females also had a liter of 4 the day before. She took 7 of the pups and put them in with that mother - she accepted them well. We were hoping the smaller liter would help Jessica to accept the babies. She said to keep them warm, and not to worry too much, but they would need to eat by that afternoon or they would die. I put Jessica's cage in a quiet room, covered by a towel, hoping she would care for them. However, at about 2, I went in to check on them. I walked in to her eating one. I let her finish, knowing there was nothing I could do, but when she went to grab another, a smacked the cage to scare her off. She dropped the baby and I quickly blocked her off and grabbed the babies into a small dish. She had obviously been staying in the opposite corner, still ignoring them. They were cold, and had not been fed. I warmed them under a light and fed them infant soy formula, again as I had read to do. I fed them every 2 hours, and could now see the milk line on them, and they were warm and active. I tried re-introducing them to her later that afternoon. She was very calm as I pet her, laying on her side, but when I put the baby in she smelled it then ran. (very possible they had been too "humanized")

(I HAVE NO IDEA ON HOW TO HANDLE THIS SITUATION... Notes for the future would be appreciated.)

That night, I returned home with Jessica and the remaining 11 pups. When my husband looked in on Sandra, we discovered she too was now a mother, to 13. She was doing great! The babies were warm, and had full bellies. She had built a suitable nest in her igloo, and was very aware of her babies. I thought this would be the solution... she could foster the orphaned pups. I put one in the cage to see if see would accept it, she smelled it, and then went back to her litter. I didn't know what to do, and didn't want all of them to die, so I decided that I would continue to care for them through the night, and would try to foster them again in the morning, once she was more adjusted to motherhood. Their last feeding was at about 11, and I tried to get all to eat well to last through the night (I had read, 2 hours between feedings, but they could make it through the night with just 1). At 3 am, all were ok, not great. They were sleeping, but I woke them up, fed them and "urinated" them, and checked the heating pad and light to make sure they were remaining warm. Most refused to even try eating, although I got a little in all.

Today - Upon wakening at AM, I had 5 living babies of Jessica's. I immediately removed those that had died. The others were still warm, and woke to my touch. I fed them. One died seconds after feeding when I placed it on the blanket, and one in my hand while refusing to eat. The other 3 didn't seem too well either. They weren't as active as yesterday, just curling up against the warmth in my hand, nudging my fingers (they thought my fingers were mom laying on them), but still wouldn't eat. I decided to put them in with Sandy's litter. I realized there was a chance of rejection, or them being eaten, but they would surely die with me as their "mom". I distracted Sandy while my husband put the 3 babies in with the litter of 13. I made sure Sandy got my scent, and touched her babies as well, so the 3 didn't stand out as badly. Once she returned to her nest, she licked the babies, then set them down, tucking them under her. I think that was her accepting them. However, when I looked in at them an hour later, all 3 were dead. They were mixed with her babies, and uninjured, so I don't think it was her rejecting them.

I live in a very small town, so I don't have a lot of resources available to me, I simply used what I could get a hold of, and did my best. They're was no advice available at that hour, and even google wasn't pulling up what I needed. Long story I know, and am sorry. But I don't know how to get a proper answer without you knowing the full history.

My questing, finally, is how should I handle this situation if it occurs again in the future? I am an extreme animal lover, and cannot willingly let animals die, no matter how "cheap they are to replace!" (I was told to just let the mother eat all of them because they are inexpensive and will breed again!) I will always do my best, so the more knowledge I have on hand, the better.

Answer
First of all, you are a VERY giving person! Many people would have given up and you did not! It warms my heart to see how much you care.

Secondly, you did everything right. Most likely, Jessica's babies did not survive due to malnutrition, not due to Sandy rejecting them after you'd already mainstreamed them. Babies need to be fed pronto otherwise they simply don't have a good start. You did very, very well trying to save them... the unfortunate part is that very rarely are you able to save newborn pups. I've tried - several dozen times - and never succeeded.

In the future, if you have two does and one is feeding and the other is not, you can foster the babies with the stable doe -- you just have to mix all the babies together and hope for the best. So basically - what you did!

I'm sorry for your losses and I really hope Sandy's litter does well.