Dwarf Rat Info. by Debbi J. Needham
DWARF RATS by Debbi J. Needham  
Re-posted 2010 - Original post 2005
The spontaneous dwarf rat (SDR) was found in a laboratory colony of Sprague Dawley rats in 1977. It is
a recessive mutation that causes them to have reduced GH or Growth Hormone which causes them to
be up 40-75% smaller than their normal-sized counterparts, and in fact, a little larger than some fancy
English mice. Dwarf rats have been found to be resistant to some cancers, as scientists have studied
the effect of chemically induced cancer on dwarf rats and found dwarfs do not develop cancerous tumors
like typically sized rats due to their lack of Growth Hormone. That is great news for those whom keep
rats in the rat fancy!

As their size has been reduced, their health, longevity and personality have not. Spike and Angel, our
first albino dwarfs, came to us as older rats. They lived around 3 years. The story goes that they were
derived from laboratory stock and were brought into the fancy and passed to rat breeders in Northern
CA. They travelled up the coast to Washington state to Odd Fellows Rattery in September 2003 where
their mild-mannered charm and incredibly mellow dispositions won the entire family over...(and many in
the Northwest rat fancy). They were exhibited at the March 2004 RatsPacNW rat show where they
were introduced to the club.

In May 2004, two more males came to Odd Fellows Rattery from Lil Rugrats Rattery in N. CA. They
were a black male named LLR Goober and an agouti male named LRR Coastal. Though their lines go
back to rats like Spike and Angel, the blocky traits of Spike and Angel have been bred out and LLR
Goober and LLR Coastal look just like standardized minature show rats.

There was discussion at the RMHF, Rat, Mouse & Hamster Fanciers Show on May 1st, 2004, that
selectively breeding for both qualities, the more classic 'dwarf' features of Spike and Angel and the
streamline features that make the rats of Lil Rugrats Rattery look like perfect sized minature rats, should
be selectively bred for and maintained. Today, there are dwarf rats actively being bred throughout the
Northwest. Some have retained the blocky, wide eyed features of Spike and Angel and others are
minature versions of their 'standard' counterparts.
by Debbi J Needham
LLR Coastal, an agouti dwarf male.
He travelled up the coast with us
from San Francisco, CA to Tacoma,
WA on April 2nd, 2004.
He was born on  3-5-04 to LLR
Dobby X Drusilla of LLR.