RAMBACH AGAR AND SM-ID MEDIUM SENSITIVITY FOR PRESUMPTIVE IDENTIFICATION OF SALMONELLA SUBSPECIES I-VI

The cultural characteristics of 112 Salmonella serovars belonging to s ubspecies I-VI were examined on Rambach agar and SM-ID medium. Colonie s showing the typical red coloration were seen with 100 of 112 serovar s assayed on SM-ID, and with 87 of 112 on Rambach agar. Atypical colou rless colonies were observed on Rambach agar with ONPG-negative serova rs S. Choleraesuis, S. Isangi, S. Typhi S. Worthington and S. Yoff of the subspecies I, S. II 52:d:e,n,x,z(15) of the subspecies II, S. IV 6 ,7:z(4),z(24):- and S. IV 11:g,z(51):- of the subspecies IV, and S. 40 :z(35):- belonging to S. bongori (V) species. Atypical blue, blue-gree n, blue-violet or violet colonies were observed on both media with all the ONPG-positive serovars of the subspecies IIIa (four of four strai ns) and IIIb (six of six strains) and with one of the two ONPG-positiv e (out of five) strains of the subspecies VI. Four serovars of S. bong ori showed blue-green colonies on Rambach agar and typical red colonie s on SM-ID, although they were all ONPG-positive. These results sugges t that SM-ID medium is more sensitive than Rambach agar. However, the relatively low sensitivity of both media makes them suitable for use o nly in association with a traditional selective medium in both medical and environmental bacteriology, as well as for epidemiological purpos es.