Feasibility of fluorescent detection of pathogens on pork carcasses

The direct immunofluorescent detection of pathogens on pork skin is evaluated. Calibrate contamination of pork skin with Salmonella Typhimurium (ST) and Listeria monocytogenes (Lm) is developed in 2 h at 4 degrees C. Then a specific indirect immunofluorescent staining protocol is optimized in order to obtain specific and intensive signals able to be detected by electronic cameras (deported microscopy). Despite the individual staining of ST and Lm is possible on pork skin and is specific and bright, the deported microscopy failed to detect these particles. After respectively 3 and 6 h, we obtain micro-colonies of ST and Lm. Due to the limited power of the video camera used, only the microscope permits the detection on the skin. However, our work gives standard conditions to mime the pathogens contamination and staining directly on a biological matrix such as pork skin. This work is a first step in the development of direct and rapid detection of pathogens on biological matrix.