How young is too for a rat to get pregnant?

Female rats (also called does or queens) are generally considered sexually mature and able to reproduce when they reach 5-7 weeks of age. However, some rats, particularly larger breeds like Norway rats (Rattus norvegicus), may reach sexual maturity earlier, even at 3-4 weeks of age.

It's generally not advisable to breed rats younger than 5-6 months old as they are still quite young and may not be fully developed both physically and mentally to support a successful pregnancy and raise a litter. Earlier pregnancies can lead to complications and health risks for both the mother and the offspring.

If you're considering breeding rats, it's essential to provide them with proper care and nutrition and ensure they are of an appropriate age and health condition to avoid potential problems during pregnancy and beyond.