Expiration
Refer to expiration date stamped on the container. The dehydrated medium should be discarded if not free
flowing, or if appearance has changed from the original color. Expiry applies to medium in its intact container
when stored as directed.
Limitations of the Procedure
1. Hemolytic reactions of some strains of group D streptococci have been shown to be affected by
differences in animal blood. Such strains are beta-hemolytic on horse, human, and rabbit blood agar and
alpha-hemolytic on sheep blood agar.6
2. Incubation atmosphere can influence hemolytic reactions of beta-hemolytic streptococci.6
For optimal
performance, incubate blood agar base media under increased CO2 (5 - 10%).