Page 130 - 2013 ISPAM Mid-Year Mtg Book

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Isolation
AOAC – XLD, HE and BS, 35°C, 24± 2h (plus BS at 48 h)
BAM (FDA) XLD HE and BS 35°C 24± 2h (plus BS at 48 h) – , , ,
MLG (FSIS-USDA) – BGS and either DMLIA or XLT4, 35 ± 2°C, 18 – 24 h
HC – any 2 of BS, BGS and Brilliance Salmonella Agar, all at 35°C, 24± 2h (plus BS at 48 h)
ISO – XLD, 37°C, 24± 3h plus a second agar that is left to the discretion of the testing
laboratory (following manufacturer’s instructions).
Considerations
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• Allowing the growth of all Salmonella serovars, or at least those known to cause food
borne illness?
Purification from Selective Plates before
Confirmation
• Not required by all methods, but MLG method does describe (very
nicely) an issue with picking directly from selective plates and
going directly to confirmation tests
• “Pick only from the surface and center of the colony. Avoid
touching the agar because these highly selective media suppress
growth of many organisms that may be viable”.
• Not an issue for PCR confirmation methods
• Is this something worth a discussion?
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