Characterization of Treponema phagedenis-like spirochetes isolated from papillomatous digital dermatitis lesions in dairy cattle.

Four spirochete strains were isolated from papillomatous digital dermatitis (PDD) lesions in Iowa dairy cattle and compared with two previously described spirochete strains isolated from dairy cattle in California. These six strains shared an identical 16S ribosomal DNA sequence that was 98% similar to Treponema phagedenis and 99% similar to the uncultivated PDD spirochete sequence DDLK-4. The whole-cell protein profiles resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of these six strains were similar.