[Detection of atypical toxin-producing Pasteurella strains on the nasal mucosa of calves and their differential diagnostic limits for Pasteurella haemolytica and Pasteurella multocida].

The bacterial colonisation on nasal mucous membranes of calves at age of 3, 5 to 5 months was investigated by cotton swabs. Three Pasteurella species were found (P. multocida subspecies multocida, P. haemolytica, P. avium) as monocausal infection as well as pluricausal infection. P. avium was characterised by colonial morphology, bacterioscopy, biochemical properties, polypeptide-pattern in SDS-PAGE and by electronmicroscopic investigation and was differentiated from P. multocida and P. haemolytica. It is very interesting, that the P. avium strains possess an antigen structure, reacting with monoclonal antibodies directed against the heat labile-toxin of P. multocida subspecies multocida.