Titrations of Various Mouse Mammary Tumor Viruses in Different Mouse Strains 2

Abstract

Milks from the high-mammary-tumor mouse strains, A, BALB/cfC3H, Rill, and C3H were titrated for infectivity in low-mammary-tumor strains C57BL, BALB/c, Af, and Rlllf. 1) There was a wide variation in susceptibility of different mouse strains to the same virus; 2) the susceptibility of each mouse strain depended on the donor virus; i.e., mice resistant to mammary tumor virus from one strain were susceptible to virus from another strain; 3) Rlllf mice were relatively resistant to the virus from the parent isogeneic Rill strain; 4) infectivity maxima of milks ranged from dilutions of 10⁻³ to 10⁻⁶.