A RAPID SCREENING METHOD FOR SALMONELLA TYPHIMURIUM DT 104 IN POULTRY BARN ENVIRONMENTAL SAMPLES

Abstract A rapid screening method was developed to presumptively identify S. typhimurium DT 104 in naturally contaminated poultry barn environmental samples. This technique involves a semiselective preenrichment (chloramphenicol in buffered peptone water) procedure followed by screening with a Salmonella-specific chemiluminescence-based detection system (IsoSCREEN™, Stratecon Diagnostics International, USA), then plating on Modified Semi-solid Rappaport-Vassilliadis (MSRV) agar plates incorporating antibiotic disks (ampicillin, chloramphenicol and tetracycline). Environmental samples (183 total) from a poultry barn were analyzed for the suspected presence of Salmonella typhimurium DT 104. Of these, 141 samples were identified as containing Salmonella species, 9 of which were identified as Salmonella typhimurium DT 104 by both the standard culture methods and the combined IsoSCREEN™-MSRV antibiotic susceptibility test (IsoSCREEN™-MAST). In comparison with the standard culture and antibiotic susceptibility testing techniques, which require 7–9 days to complete, the IsoSCREEN™-MAST required only 3–5 days to presumptively identify Salmonella typhimurium DT 104 in the samples.