The dwarf rat is more than just a miniature version of the standard sized rat! In the article below, I attempt to provide information about the general care, handling, and breeding of the dwarf rat- for those considering the adoption of this new gem of the rattie world.
The image on the left, is a burmese dumbo smooth coat male. The image on the right is a top eared velveteen self male.
There is no doubt that what the dwarf rat lacks in size they make up in personality. The dwarf rat, is a high energy, courageous, and sweet little rat.
With that being said, care must be taken when interacting with them for obvious reasons. Often times what people love about the standard sized rat is their curious and sometimes laid back nature. The dwarf, on the other hand, is very curious, but instead of a quiet snuggler, they are highly active! In fact, if they hear a strange sound, they will often run to it, in an effort to investigate! As another example, when you open the cage they all come, "pouring out," as one breeder-friend experienced. Further more, many dwarfs are seen hanging from the top of their cage, or are quick to hop off your shoulder to investigate the desk top...!
This is not to say that they are unpredictable and unfriendly! On the contrary! All of my dwarfs have amazing personalities that are all very unique!
When handling a dwarf, remember that they are light and fast moving. Try to position yourself in a brightly lit room on a chair or couch, as this may help you prevent injury if they fall, or escape.
While I have indicated that they are sometimes very active, there are some dwarfs that are not as active as the typical dwarf rat. I actually own a male dwarf out of standard sized parents that is very calm. He will just hang out on my shoulders for a half and hour and has even fallen asleep bruxing under the layers of my shirt.
Dwarf rats also bond in amazing ways, just like standard sized rats! A while back we had a female born in a litter of standard sized rats. At first, this female was the same size as her brothers and sisters. Then around 4-6 weeks, they had a considerable growth spurt leaving her behind! We kept this little girl and named her Zoe! She is an amazing rat, that has learned her own name, and has acquired the most delightful manners! No matter how long you allow her to sit upon your shoulder, Zoe does not go potty until she is returned to her cage!
Lastly, the dwarf is smaller, more active but just as lovable as the standard rat. They make great pets for the right type of owner.
The dwarf rat is approximately 1/3 the size of the adult standard rat which can be 9-11 inches long and on average 1.5lbs. Although, they are smaller, the dwarf rat tends to have more energy than the typical Standard rat, As a result, they still require the same types of housing as the larger adult standard rat with a few exceptions.
To give you an idea of the size difference between the dwarf and standard sized rat, consider this picture to the left, a young blue 4 month old female standard sized rat and a young 3 month old female Burmese dwarf. Here is a picture (below) of a dwarf rat, named Zoe, that is full grown, in my hand.
The dwarf rat is an active climber. What ever cage you decide on make sure that it is the largest cage you can reasonably afford with appropriate bar spacing of 1/4 inch or less. They enjoy climbing up the sides of their cage and even dangling from the top with their amusing dare-devilish stunts!
I have taken the time to redesign large storage tubs and converted them into suitable housing for the dwarfs at our rattery. They seem to love the screened tops and sides for climbing and all of the other goodies that we have available for them. There are actually four dwarfs living in this tub. There is plenty of space for them to run around and the sides have been fitted with safe wire that enables them to double the space available on the inside of the cage for climbing and hanging other fun items. There are two wheels- which I keep careful watch of their little feet to make sure that the surface of these wheels do not injure them. So far, there doesn't seem to be any problems!
If you look carefully in the picture, you will see a cube hammock, which they absolutely love to snuggle in and on top of!
Dwarf rats love toys and hammocks just as much as standard rats do. I provide my dwarfs with a variety of Hammocks, paper rolls, boxes, ladders, wheels, chew toys, fleece ropes, and more. My creativity knows no bounds when it comes to thinking of new additions to the dwarf cages. Half of the fun is watching them playing with their toys!
Other toys that are shown above are the rawhide bones and the Hol-ee Roller, a cool dog toy that is hung from the top of the cage. I put veggies in them and they have fun trying to climb and tug to get the food out!
Some people have asked whether dwarf rats can be successfully kept with standard sized rats. Some breeders feel that this must avoided at all costs because standard sized rats have been known to be very aggressive towards dwarf rats. Yet, other breeders feel that as long as the standard sized rats have grown up with the dwarf rats, that there shouldn't be a problem. I would also not recommend adding a dwarf rat kitten(s) in with an established group of rats that had no prior exposure to dwarf rats. We currently have three male dwarfs housed with two standard males (all cage mates since they were kittens) and there have been no issues.
We offer all of our standard rats a diet that consists of 50% Senior low-fat dog food, 30% fruit and vegetables and 20% lab block grain mix (that we mix ourselves).
The dwarfs are fed the same diet, however, it is recommended that they are given a diet that is slightly higher in protein. Two breeders, who have worked with dwarfs for several years, have been successfully providing a diet that contains around 16% protein, levels typically found in puppy food. The higher fat and protein content of these feeds supply the energy demand of these active dwarf rats with what they need to grow and maintain an appropriate body mass.
As pet dwarf rats become older, 12+ months, you can feed them a lower protein diet as long as they are fed a great variety of fresh foods. Females used for breeding should be fed higher protein before, during gestation, and during lactation in addition to the rest of their daily ration of grains, fruits, vegetables, and yogurt.
There is much work to be done, so to speak, in the development of the health, longevity, type, and behavior of the dwarf rat. Some dwarf lines are very healthy and have gentle dispositions, however, there is always room for improvement. Therefore, breeders are reluctant to allow their lines to be distributed to anyone beyond pet adopters and even then, dwarfs are certainly not for everyone.
The picture, above right, is a young female dwarf that is a double velveteen. When she reached ~5 weeks, she moulted and had no hair for several weeks! Slowly, her coat returned and now she has a thick soft wavy velveteen coat!
The dwarf-gene is a recessive mutation that occurred in a standard sized rat. The mutation causes a decrease in the production of growth hormone resulting in a smaller size-hence dwarfism. There are several ways to breed dwarf rats. It is best to pair a male dwarf to a female dwarf. This pairing would result in 100% dwarf offspring.
Some breeders have had success pairing an adult sized male dwarf with a young female standard sized rat (~4 months old). This method might be appropriate for a breeder who has only male dwarfs and no females of the same type. They might also utilize this method as a means to improve health and type. It should be noted that there is always risk when breeding female rats when they are very young. It should be done with care. In any event, this would produce all standard sized babies (as long as the mother does not have a copy of the dwarf gene). The offspring would carry one copy of the dwarf gene, from their father. Once the offspring from this pairing mature, the most appropriate siblings can be paired for a 25% chance of any baby being born dwarf.
Lastly, a breeder can pair a female rat that carries the gene for dwarfism to a male dwarf and from this pairing there should be a 50% chance of any baby being born a dwarf. Keep watch any time you pair up standard sized rats with dwarf rats. Standard sized rats have been known to kill dwarf rats.
The chart to the right illustrates a variety of methods used to produce dwarf rats.
I have done some research by investigating information on various reputable websites, in addition to several impromptu interviews with breeders/friends, who have been working with dwarfs, to find out the differences between breeding and caring for the dwarf rat in comparison to the standard rat. Like the standard rat, the female dwarf rat, is bred for the first time around 6-7 months of age. The typical litter size is smaller (2-6), on average, in comparison to the standard rat, which is 13-15 kittens per litter. Dwarf rats are reported to be excellent mothers that properly care for their young. There are instances where females are not as "emotionally mature" at 6 months to take on the burden of raising young. In addition, it has been recommended that females are only bred twice in their reproductive life time, once at 6-7 months and for the last time around 10 months of age. Two breeders reported that there is a high occurrence of still born kittens in litters born after the mothers 12th month.
Due to their more delicate nature at four weeks, breeders are strongly advised to wait until 6-8 weeks to adopt out dwarf rats so that they have time to further develop. During this time, changes affect their physical development and how they interact with their outside world. The extra time with a good breeder is used to expose them to a predictable, safe, and loving environment so that the kittens are well-adjusted when they come to live in the new adopters home.
Finally, breeders happily report that dwarfs live just as long as the average standard sized rat of 2-3 years!