Improved Isolation of Anaerobic Bacteria from the Mouse Gecum By Maintaining Continuous Strict Anaerobiosis

SummaryTwo technics for anaerobic culture were compared for their efficiency in isolating anaerobic bacteria from the cecum of the mouse. A conventional method using a broth diluent and blood agar plates incubated in anaerobic jars recovered only 1.1-5.8% of the total number of bacteria present. In contrast, 19.7-33.7% of the total bacterial count was recovered when the specimen was processed by the Hungate technic, which entailed anaerobic collection, dilution in reduced fluid under CO2 and culture in roll tubes. Many of the bacteria isolated in this manner did not grow at all on blood agar plates incubated in anaerobic jars. The data presented indicate that the predominant, strictly anaerobic bacteria of the cecal flora were sensitive to even transient contact with atmospheric oxygen.