Division 4.1 Sample preparation for bacteriology

Lymph nodes shall be surface de-contaminated before analysis by dipping into absolute alcohol and drying by air.

All lymph nodes shall be pooled and closed in a plastic bag and banged with a hammer or so on the plastic bag smashing the lymph nodes.

The homogenised lymph nodes shall be weighed and placed in a sterile container with pre-warmed buffered peptone water (BPW) in dilution 1:10. Containers shall be incubated for a total of (18 ± 2) hours at (37 ± 1) °C.

Regarding swabs sample, at the laboratory, 100 ml of BPW shall be added for pre-enrichment. The sample shall be incubated at 37 °C overnight and examined for Salmonella using the modified semi-solid Rappaport-Vassiladis medium (MRSV) method (draft Annex D of the ISO 6579:2002(E).