What are the recommended breeding ages (upper and lower) for female rats?
Female rats can get pregnant as early as five to six weeks of age, but they really should not be bred until they are three and a half to four months of age. If they are not bred at that time, they should be bred (if you plan to breed them at all) before they are eight months old. If they have a litter between these ages, you can breed them up until about one year, but it is not recommended breeding beyond that. If they have not been bred by eight months of age, their chances of conceiving go down as well. Being overweight will also reduce their chances of getting pregnant.
