[Antigenic structural studies of S. aureus strains in mastitis in cows]

Studied were the antigenic behaviours of S. aureus strains isolated from mastitis-affected cows on ten dairy farms, using factorial immune sera obtained against human S. aureus strains of a known antigenic structure. One hundred fifty (57 per cent) out of 263 strains proved typable, while 113 (43 per cent) did not produce positive agglutination reaction with any of the factorial sera. Considerable variation was established within the antigenic structure of S aureus. The k1, k2, b1, c1, n, and m antigens were most frequently encountered.