A MORPHOLOGICAL CHARACTERIZATION OF BORRELIA-ANSERINA

The morphology and ultrastructure of two strains of Borrelia anserina were investigated by electron microscopy of negatively stained and ult rathin sectioned cells. One was a cultivable strain originally isolate d in the USA and the other was originally isolated in Nigeria and main tained in chickens. The cells were regularly helical, 9-21 mu m long a nd 0.22-0.26 mu m wide with a helix wavelength of about 1.7 mu m. The cells were surrounded by a surface layer and appeared to divide by bin ary fission. The structure of the cells from each of the two strains w as identical except that those of the USA strain possessed seven flage lla inserted at each end and those from the Nigerian strain had eight.