[Pasteurella haemolytica serotyping].

Forty-nine strains of Pasteurella haemolytica were serotyped in a pilot study. The majority of strains were isolated from sheep which had died from fibrinous pneumonia and small numbers from cases of sepsis, polyserositis, mastitis and meningitis. Serotype A2 was found to be the most prevalent: 69.4 per cent. In addition, serotype A7 with 18.4 per cent and serotypes A1 and A6, both 6.1 per cent, were identified. Biotype T strains were not detected in this study. Further research is required into the seasonal prevalence of P. haemolytica serotypes in sheep and cattle. This knowledge may help to improve herd health schemes for sheep and cattle in the Netherlands.