Breeding of Tester Strains for Coat Colour Genes

Abstract

It should be noted that homozygosity for coat colour genes does not represent a purify of the given strain, but heterozygosity for coat colour genes definitely denotes a heterozygous animals.
As all of pure strains are homozygous for the genes, in order to check up and avoid mistakes in mice breeding, testing of the gene constitution may be an effective method.
For the benefit of the testing, two tester strains for coat colour have been bred up and maintained by sib-mating. They are named I-tester, and II-tester and their genetic formulas are as bb CC D/d ss and as bb C/c dd ss respectively.