Introducing Dwarf Rats to Ratology Tales!

My introduction to dwarf rats is an unusual one and shows that almost anything can pop out of a line. 

The original line stems from BWR's variegated/dalmatian line. I obtained a black variegated male and an agouti variegated female from her in February of '17. I paired these two rats and kept back the best of the litter, resulting in a black variegated female named Florence and a male variegated named Harper. I paired these two together later summer and on September 15th, Florence gave me a beautiful litter and a wonderful surprise. Three dwarfs, little Loki, a male agouti variegated, Frigga, a female agouti variegated, and Sif, a female black variegated. This line shows no dwarf for the past 5 generations in the pedigree so the fact that I do have it is a stroke of luck. That being said, ratteries in the pedigree do have dwarf in their rattaries. 

Weights at ten weeks old. 

Loki - 90 grams
Sif - 75 grams

Frigga - 72 grams

Compared to them, their standard sized sister is 215 grams. 

So what is a dwarf rat?

Dwarf rats are also called spontaneous dwarf rats, SDR, and have been extensively used in research due their limited growth hormone which also effects the way cancer grows. Because of this, a little more is known about this particular mutation, or variety, of rats. Dwarf rats appear, in research, to be less prone to cancer such as mammary tumors and may live longer than your standard rat. They are, in fact, a smaller version of a standard rat. They are healthy and robust as a standard rat and are just smaller.

As stated above, dwarf rats are smaller because they have a limited amount of growth hormone. This growth hormone difference is seen between 2-6 weeks in a litter. Many times a dwarf baby will appear much like its standard siblings, just as healthy, big and strong. Between 2-6 weeks (typically), they start to appear smaller than their siblings in more than just body shape.  The feet will be smaller, more petite, the tails will be short and less thick, even their faces are more demure. Some have these big gigantic eyes giving them this adorable look. Size wise, they are about 1/3 the size of a standard rat.

Dwarf is a simple recessive gene meaning both parents must either carry, express or one of each in order to get more dwarfs. There is evidence of dwarfs being extremely active, brave and in some cases high strung. The three current dwarves in my litter are all calm and very sweet. If that changes, I will update.

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How do I tell if I have a dwarf rat?

Here is my disclaimer and warning for those wanting dwarfs. I came across these dwarfs in a litter that I did not expect to find dwarfs. The rats originated from another breeder. It is not easy to find and what happened to me was one in a million. Be wary of those selling dwarf rats, especially if they look sickly. Breeding rats smaller and smaller does not make a dwarf and can result in ill side effects. If your rat weighs more than 150 grams, the likelihood of your rat being dwarf is very slim. 

This variety is brand new to me and will not be leaving my rattery this generation. My goal with this dwarf line is to make pearl merle dwarfs!

So welcome to the rattery, my little dwarf babies!

As of 11/24/17, Florence and Harper have given me another litter and so far I have two dwarfs that I can tell, both males.