A male rat "SRR-Do Your Best" was introduced from American fancy rat colony (Spoiled Ratten Rattery: SRR, in Kansas City, Missouri) to Kyoto University on July 13, 2005. Inbreeding started from F1 progeny of male "SRR-Do Your Best" and a female PVG/Seac.
Maintained by crossing of homozygous and satin heterozygous. Poor breeding performance. Young females and old males are suitable for breeding. Id est, we start smear test at 7 weeks of age and cross females with their father (parent-offspring mating).