GROWTH DIFFERENCES OF CAPNOCYTOPHAGA-CANIMORSUS STRAINS AND SOME OTHER FASTIDIOUS ORGANISMS ON VARIOUS COLUMBIA-BASED BLOOD AGAR MEDIA

Three human isolates of Capnocytophaga canimorsus from blood cultures showed no growth when cultivated on sheep blood agar Flares based on B BL Columbia agar base, whereas the same three strains grew excellently on sheep blood agar plates based on Difco Columbia agar bases No. 2 o r EH. Two of the three strains also grew well on blood agar plates bas ed on bioMerieux Columbia agar. Strains that grew better on either Dif co or bioMerieux Columbia based blood agar plates were found among Eik enella corrodens, Haemophillus aphrophilus, Kingella kingae, Lactobaci llus sp., and Streptococcus adjacens, but these strains were never los t when cultivated on BBL Columbia agar plates. One strain of Lactobaci llus failed to grow on Difco Columbia No. 2 agar and showed best growt h on bioMerieux Columbia agar. Strains of Corynebacterium G 2, Coryneb acterium afermentans and Streptococcus adjacens showed poor growth on chocolate agar when compared to blood agar media. Microbiologists shou ld be aware of the importance of media formulations for optimal recove ry of fastidious organisms.