Deciding to breed your Roborovski dwarf hamsters is not a decision to make without doing your research first and you absolutely must consider what you will do with any babies that will result. Most pet stores already have established suppliers and there is no shortage of hamsters available from these large suppliers. They simply have no need for hamsters bred by you. You should also carefully consider the temperament and health of the hamsters you are breeding so that your offspring can be the friendliest dwarf hamsters possible.
The information here may be helpful if you find yourself with an accidentally pregnant female (whether it happened while in your care or she was purchased from the pet store already unknowingly pregnant).
Age of Sexual Maturity of Roborovski Dwarf Hamsters
Roborovski dwarf hamsters can reach sexual maturity as early as 5 weeks of age, but they usually do not breed for the first time until they are older. Females should be bred for the first time when they are closer to 4 months old (males can be bred by 3 months of age). Roborovski dwarf hamsters are considered more difficult to breed than Dwarf Winter White Russian hamsters or the larger Syrian hamsters. Also, Roborovskis may be more likely to breed only in spring and summer months and a female might not have her first litter until her first spring.
Hamster Heat Cycles
Female hamsters come into estrus (heat) every 4 days or so (this is the time they will be fertile and receptive to a male).
This means the opportunity for your hamster to get pregnant is practically constant!
Length of a Roborovski Dwarf Hamster Pregnancy
The gestation period (time your hamster is pregnant) of Roborovski hamsters is usually 20-22 days can be up to 30 days. This is a very short time for an animal to be pregnant (but Syrian hamsters are only pregnant for about 16 days) so you won't have to wait long to see whether or not your hamster is having babies if you suspect she is pregnant.
After a couple of weeks, your female hamster will start to develop bulges on her sides indicating she is pregnant. It may be hard to tell if your hamster is pregnant if she is also overweight.
How Many Pups Do Roborovski Dwarf Hamsters Have in a Litter?
Litter size for Roborovski dwarf hamsters is usually small. There are typically between four and six pups in a litter but larger litters are not unheard of. Larger breeds of hamsters such as Syrians have been known to have litters of over 20 pups! Pups are born pink and naked with their eyes closed. They are fully reliant on their mothers who will nurse them, keep them warm, and clean them until they get a little older.
Weaning Age of Roborovski Dwarf Hamsters
Roborovski dwarf hamsters can be weaned from their mother at 21 days of age. This is also a good age to separate the male pups from the female pups in the litter since sexual maturity may be reached by as young as five weeks of age. Your exotics veterinarian should be able to help you sex the pups so that you can separate them. Make sure your hamster pups are eating on their own prior to taking them from their mother. Your hamster pups will be ready to go to their new human parents once they are weaned but it is usually recommended to hang onto them for another two weeks just to make sure they are eating well.
Edited by Adrienne Kruzer, RVT