Modified Semi-Solid Rappaport-Vassiliadis (MSRV) Agar

Modified Semi-Solid Rappaport-Vassiliadis (MSRV) Agar is a selective medium historically used for the isolation of Salmonella in chocolate and other food products. It is also widely used in animal health: in particular with mammals, poultry, and in animal production facilities. It is also recommended for use in the detection of motile Salmonellae in animal fecal matter and in environmental samples in the context of primary animal production.

The medium is not recommended for immobile Salmonellae (Salmonella Gallinarum et Pullorum). If the presence of these strains is suspected, the cultures obtained with preenrichment media must be transferred to appropriate media using conventional standardized procedures.

The typical composition responds to that defined in the standards NF EN ISO 6579-1/a1, NF U47-100, NF U47-101, and NF U47-102.

Principles

• Bacteriological efficacy is based on the capacity of salmonellae to selectively migrate in the medium
• High concentration of magnesium chloride and the presence of malachite green inhibit contaminating bacteria
• Addition of novobiocin inhibits most gram-positive bacteria and avoids the development of
• Salmonella produce an opaque halo, a reflection of growth