The biochemical properties of strains of Staphylococcus aureus isolated from cattle with peracute gangrenous mastitis, acute systemic mastitis and chronic mastitis were examined.
Of 261 strains of Staphylococci isolated from quarters with clinical mastitis,140 (53.6%) were classified as Staphylococcus aureus and 121 (46.4%) were coagulase-negative staphylococci.
All the strains of Staphylococcus aureus isolated from quarters with peracute gangrenous mastitis and acute systemic mastitis showed production of alpha heamolysin, coagulase, lipase, phosphatase, nuclease and gelatinase, and fermentation of mannitol. However, of 114 strains of Staphylococcus aureus obtained from quarters with chronic mastitis, 64 (56.1%) possessed alpha lysin, and 43 (37.7%) produced lipase in egg yolk medium. The most common hemolytic pattern of the strains associated with chronic mastitis was βδ type.
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