[A new method for the demonstration of the Bordetella bronchiseptica capsule in electron microscopy]

A new and rapid working method is presented for electronmicroscopic preparation of capsules from gram negative bacteria, e.g. Bordetella bronchiseptica and Pasteurella multocida. The advantage of the new technique is the availability of the results within 30 min after starting the preparation. The staining of the capsule by alcian blue has to be done as a first step together with glutaraldehyde fixation, before staining the bacterial cell with phosphotungstic acid. The new staining technic also reveals structural details of the capsule. The described procedure was found to be useful in controlling the development of the bacterial capsule depending on culture media for propagation and maintenance of the above mentioned bacteria.