Members of the phylum Spirochaetes (trivial name: spirochetes) have a very special morphology. They are very thin and rather long (about 0.1-0.3 x 10-20 µm) and spiral shaped. However, in the case of members of the genus Borrelia, the spiral is planar and the morphology is referred to as a “planar flat-wave morphology”. All spirochetes have periplasmic flagella (also referred to as endoflagella or axial filaments) which make them very motile. The motility in combination with the shape make it possible for these bacteria to “swim” in higly viscous media, like mucous membranes.
Phase contrast photomicrographs and improved dark field photomicrographs of living Borrelia burgdorferi have now been included in VetBact. Dark field photomicrographs of living Borrelia anserina (the fowl spirochetosis agent) have also been included in VetBact. The Borrelia anserina strain was obtained from Bilal Aslam (Inst. of Microbiology at the Univ. of Agriculture, Faisalabad, Pakistan).