[Hyalurodinase activity of beta-hemolytic streptococci of the Lancefield group C].

A total of 110 strains of beta-hemolytic streptococci, belonging to serogroup C (Lancefield), isolated from horses (71 S. zooepidemicus, 27 S. equisimilis and 12 S. equi) as well as 5 reference strains were tested for their ability to produce hyaluronidase. The determinations were carried out in a culture test on agarose gel and in a liquid test system (turbidity test according to DiFerrante). The results of both methods used showed that the three Streptococcus species could be differentiated by the relative quantitative determination of hyaluronidase activity. S. equisimilis strains produce 5 to 10 times more hyaluronidase than those of S. zooepidemicus. The strains of S. equi did not show enzyme production. In addition parallel tests by determination of final N-acetyl-D-glucosamine groups and by turbidity test were done to confirm the hyaluronidase activity of S. equisimilis strains. The comparison of results (Fig. 3) obtained from these tests, showed a good correspondence as demonstrated by a correlation index of 0,93.