[Use of+Rambach agar for the detection of Salmonella in feces using broth enrichment. Comparison with our methodology].

BACKGROUND

A comparative study between Rambach agar and our previously published methodology (Salmonella-Shigella agar + C8-esterase test) was carried out to isolate Salmonella from 815 stools samples after enrichment in selenite broth.

METHODS

On Rambach agar all pink and colourless colonies which were oxidase negative and red colonies were also identified. On SS agar, black colonies and colourless colonies which were oxidase negative and C8-esterase test positive were identified biochemically.

RESULTS

One hundred and twenty-three colourless, 81 pink and 112 red colonies grown in Rambach agar, and they were subcultured in Kliger agar yielding 7, 2 and 109 Salmonella, respectively. From SS agar, the 113 black and 10 colourless colonies which had previously been positive in the C8-esterase test and oxidase-negative, yielded 113 Salmonella strains (111 and 2, respectively).

CONCLUSIONS

Rambach agar is an excellent media for isolating Salmonella after enrichment in selenite broth. If all colourless and pink colonies are further investigated the number of isolates will increase although the workload will increase, too. Therefore, it would be interesting to study a combination of C8-esterase and Rambach agar since it could reduce the workload.