Novel Propionibacterium infection in cattle

Objective To describe four cases of infection in cattle, from geographicall y different places, with a presumptive new species of Propionibacterium, wh ich causes granulomatous lesions in the head, thorax, abdomen, pelvic area and skin. Procedure Gross lesions, ranging from 0.5 to 15 cm and detected during rout ine carcase inspection at the abattoir, were submitted to the laboratory fo r routine testing in the National Granuloma Submission Program. The bacterium isolated was identified using morphological characteristics, biochemical reactions, cell wall components, products of fermentation and 1 6S rRNA gene sequencing. Results Gross lesions submitted for examination consisted of a fibrous oute r capsule enclosing thick yellow pus-like material. A Gram-Glynn stain of t he histological sections revealed colonies of Gram-positive, filamentous, b ranching bacteria. Bacteriological culture, cell wall analysis, biochemical reactions and 16S rRNA sequencing identified the organism as a Propionibac terium sp closely related to P cyclohexanicum and the P freudenreichii clus ter. Conclusion This is the first report of a Propionibacterium sp closely relat ed to P cyclohexanicum and the P freudenreichii cluster associated with ext ensive granulomatous lesions in cattle in Queensland. Sequencing data are s uggestive of a previously undescribed species of the Propionibacterium genu s.