Adaptation of lactic streptococci for growth with their homologous bacteriophage

The adaptation of lactic streptococci for growth with their homologous bacteriophage was studied through the addition of bacteriophage filtrate to skim milk medium inoculated with Streptococcus lactis or Streptococcus cremoris. Both S. lactis and S. cremoris attained their adaptability for growth with their homologous bacteriophage after 5 and 2 transferes, respectively, and did not lose it after a storage period of 30 days at 0 degree C.