Several Rat Questions

[Daigga]

Does anybody have any idea why baby rats getting ready to be weaned suddenly die? They have no marks on them whatsoever. Do you feed off older females that have obvious tumors? Do you find that older females that have small litters let their babies all die?

Any females with obvious health problems need to be culled IMO. It's better for them and for your colony as a whole. Any females that neglect their litters or seem to have hidden problems (like their offspring suddenly dying for no obvious reason) should also be culled for the same reason. Ideally, you want your females to be healthy, produce large litters, and care for them well until it's time for the pups to be taken away. It sounds like you may need to contact some local rat breeders for some better breeding stock if you're having problems like these often.

Are you giving your girls a break between litters? Over breeding females could be a cause of various health problems and/or small litter sizes. I kept my colony on a 12 week rotation when I had it, giving each tub of females up to 4 weeks to rest after weaning a litter to regain everything that birth and baby raising takes out of them.