There are many myths and misconceptions surrounding these little creatures. Some claim that the breeding of dwarf rats is unethical, while others argue that dwarf rats are just as healthy as their standard counterparts. There is far more proof pointing towards the latter - that breeding the dwarf gene, when done responsibly and properly, is perfectly okay.
The dwarf gene is very similar to the dumbo ear gene. It began as a spontaneous mutation in 1985. It is a recessive gene, meaning that 2 dwarf parents will produce a full dwarf litter, while 1 dwarf and 1 standard rat will produce a mixed litter. Dwarf rats lack the growth hormone, having approximately 6-10% that of normal rats. This keeps their size small while their proportions are completely normal. Dwarf rats are just as healthy as standards and due to the low concentrations of growth hormones, are actually much more resistant to tumors.
Dwarf rats remain tiny, ranging from 1/3 to 1/2 the size of their standard cousins.
If you choose to add a dwarf rat to your family, spend time researching breeders and be cautious. Untrustworthy backyard breeders will sell runts or sick rats as dwarf due to their smaller sizes. Some may even sell African Soft Furred rats as dwarf rats, although they are mice and will be killed if placed with rats.
I purchased mine from a responsible breeder that belongs to, and shows, with the AFRMA. I was happily surprised to hear that she keeps standards and dwarf rats together without issue. I chose to do the same, placing my mouse sized dwarf with my standards because my rats are very accepting of newcomers. If your rats are peaceful, you can do the same. I recommend following the introduction guide and keeping an eye out for any aggressive behavior.
Pictured above is our newest addition, Sprite. She's a ruby eyed Siamese. True to what I've been told about dwarf rats, she is a ball of energy and rarely sits still! They have more energy than that of a young standard female, and remain that way for much of their lives. Climbing and running is a favorite past time so it's a good idea to purchase a wheel for your dwarf rats.
While their small size might suggest otherwise, dwarf rats cannot be treated like hamsters! They need just as much space as a standard rat - if not more due to their high energy. They cannot be housed in hamster cages or tanks either. Use our cage calculator to see if your cage is large enough to house rats.
Dwarf rats do make great pets just like regular ratties, but they're not recommended for new rat owners or young children. They're small in size but big in personality!