Inhibitory Action of Various Plating Media on the Growth of Certain Salmonella Serotypes

The growth of 68 strains of Salmonella typhi , 697 other Salmonella strains and 213 strains of other Gram negative intestinal bacteria on 8 plating media was assessed semi‐quantitatively. These media were found to be differentially inhibitory to different Salmonella serotypes. The combined use of two plating media, brilliant green MacConkey agar and deoxycholate citrate agar, allowed potentially the recovery of the maximum number of Salmonella strains. If only one medium was used, brilliant green MacConkey agar would appear to be the best plating medium for the isolation of non‐typhoid salmonellas in general and S. choleraesuis in particular. Xylose lysine deoxycholate agar, on which a certain proportion of salmonellas failed to yield typical, recognizable colonies, was found not to be a good plating medium for their isolation.