Virulence for mice of Staphylococcus aureus strains from bovine mastitis related to colonial morphology and serological types in serum-soft agar.
Six Staphylococcus aureus strains isolated from bovine mastitic milk representing the typical growth types in soft agar media were injected into mice via the intraperitoneal route. Strains showing diffuse colony morphology (DCM) in serum-soft agar (SSA) as a permanent characteristic which reacted against anti-capsular sera types A, B, and D were virulent for mice. A strain showing DCM in SSA that reacted only against anti-capsular serum D behaved as a compact-colony-morphology-type strain in the peritoneal cavity of the mouse. Diffuse-type colony morphology and presence of capsular antigens type A, B, and D correlated with increased virulence for mice, but a capsule could not be demonstrated.
Department of Large Animal Clinical Studies, Faculty of Veterinary Medicine, University College Dublin, Ireland.
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Calvinho
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Dodd
D000818:Animals; D002417:Cattle; D003470:Culture Media; D005260:Female; D008297:Male; D008414:Mastitis, Bovine / Q000382:microbiology*; D051379:Mice; D008892:Milk / Q000382:microbiology; D011817:Rabbits; D012703:Serotyping; D013203:Staphylococcal Infections / Q000382:microbiology / Q000662:veterinary*; D013211:Staphylococcus aureus / Q000145:classification / Q000254:growth & development / Q000472:pathogenicity*; D014774:Virulence
D003470:Culture Media