A substrain mouse serologically classified in ddN strain and its behavioral characteristics

A special substrain mouse in ddN strain was classified by cross agglutination reaction of the red blood cells with anti-ddN mice red blood cells rabbit immune serume. The agglutination reactivity in the full-grown substrain mouse was as high as in an infant ddN mouse. Incidence of the substrain mouse in ddN strain aged older than 9 weeks was about 10%. The full-grown substrain mouse revealed a form of excitation after long-term administration of methamphetamine while other mice in the same strain were depressed. The behavioral and serological properties of histocompatible strain mice such as C57Bl and C3/ were studied to compare with those of the ddN substrain mouse.