Reactivity of coagulase-negative staphylococci isolated from cow and goat milk with monoclonal antibodies to Staphylococcus aureus capsular polysaccharide types 5 and 8

Monoclonal antibodies to Staphylococcus aureus capsular polysaccharide types 5 and 8 were used in an enzyme-linked immunosorbent assay to serotype 74 and 42 coagulase-negative isolates from cow and goat milk, respectively. Eighteen (15.5%) isolates were typable: 13 Staphylococcus haemolyticus, 1 S. hyicus, 1 S. simulans, and 1 S. warneri from bovine origin and 2 S. lentus from caprine origin. Type 5 was predominant, accounting for about 89% of typable isolates. Reactivity with monoclonal antibodies varied considerably according to isolates. The significance and the potential importance of these findings are discussed.