Division 2 Sample processing

Swabs if submitted ‘dry’ must be placed in sufficient antibiotic medium to ensure full immersion. Samples may be pooled in batches in batches of five provided they are derived from the same species, time and epidemiological unit.

Carcases submitted to the laboratory must be subjected to post mortem examination and samples of the following organs must be taken: faeces or intestinal contents, brain tissue, trachea, lungs, liver, spleen and other obviously affected organs. Those organs and tissues may be pooled, but separate treatment of faecal material is essential.

Faeces samples and organs must be homogenised (in an enclosed blender or using a pestle and mortar and sterile sand) in antibiotic medium and made to 10 to 20 % w/v suspensions in the medium.

The immersed swabs and suspensions must be left for approximately two hours at ambient temperature (or longer periods at 4 ^oC) and then clarified by centrifugation (for example, 800 to 1 000 x g for 10 minutes).