Forty growth-factor independent Pasteurellaceae strains representing most known taxa from rodents and rabbits were API 20 NE profiled by four laboratory animal diagnostic laboratories using their routine methodology. Significant differences were found in the number of bacterial strains classified with the Pasteurellaceae. The results of the four laboratories taken together showed that 136 (85 %) of the 160 tests carried out with the 40 strains led to classification with the family. The 23 Pasteurellaceae strains from species (Pasteurella aerogenes, P. multocida, P. pneumotropica) present in the API 20 NE data base (API taxa strains) and the 17 strains from taxa not included (non - API taxa strains) were classified with the family with similar frequency.Pasteurella species designation differed significantly between the laboratories and full agreement in speciation was found with only 9 (22.5 %) of the 40 strains. Of the tests carried out with P. multocida and P. pneumotropica, 42 and 52 % respectively led to misclassification. Conversely 38 % of the profiles obtained with non- API taxa strains led to identification as P. multocida or P. pneumotropica. We conclude that identification of Pasteurellaceae to the species level by the API 20 NE system is unreliable, but the system is useful to classify various Pasteurellaceae taxa from rodents and rabbits with the bacterial family.
