[Biochemical properties of different serotypes of Pasteurella haemolytica]

Studied were the morphologic and biochemic properties of 85 Pasteurella haemolytica strains belonging to the known 12 serotypes after Biberstein, Gills (2). The biochemical properties of the strains were studied after the pattern of Bosworth and Lovell (4) with regard to arabinose, trehalose, xylose, manose, salysin, and lactose. It was found that the biochemical properties correlated with the biotype classification of the strains. Thus, the biochemical reaction with trehalose and arabinose may be used as a characteristic feature in determining the biotype. The reaction proved more dependable with the strains of the T biotype as compared to those of the A biotype, as not all strains of the A biotype fermented arabinose in the course of the first seven days, while with the strains of the T biotype trehalose was acted upon during such a period. It was also established that xylose is attacked by the strains of the A biotype only, and manose and salycin--by the strains of the T biotype, which did not ferment lactose. All strains of Pasteurella haemolytica turned out to be negative so far as the production and indol was concerned; they were shown to reduce the nitrates into nitrites, were MP and VP negative, and gave growth in McConkey's agar medium.