DISCRIMINATION OF STRAINS OF SALMONELLA-ENTERITIDIS WITH DIFFERING LEVELS OF VIRULENCE BY AN IN-VITRO GLASS ADHERENCE TEST

The objective of this study was the in vitro differentiation of isolat es of Salmonella enteritidis whose virulences differed in a chick mode l. A total of 14 strains of S. enteritidis were isolated from either t he environment, dairy products, or infected patients. The isolates cou ld be divided into two groups on the basis of their virulence (50% let hal dose) in chickens infected intraperitoneally. When the strains wer e incubated in adherence test medium (Spanish patent 9700408), only th e virulent strains produced aggregates and formed visible filaments at tached to the glass tube. These results suggest, although for a limite d number of strains, that aggregation in such a medium could be used a s a diagnostic tool to discriminate virulent strains of S. enteritidis .