A note on the effect of different storage procedures on the ability of Preston medium to recover campylobacters.

The effect of different storage procedures on the ability of Preston medium to recover campylobacters was investigated. Freshly poured media was shown to recover more campylobacters than media stored under aerobic or anaerobic conditions at room temperature or at 4 degrees C. The growth of Campylobacter laridis was greatly reduced by storage of media and although most strains of C. jejuni and C. coli were not markedly affected, the growth of one strain of C. jejuni was considerably reduced. It is recommended that freshly prepared media be used whenever possible, but if storage is necessary, then plates should be held at 4 degrees C, preferably under anaerobic conditions. These precautions may not be necessary for workers interested solely in C. jejuni or C. coli, but are essential for the optimum isolation of C. laridis.