An Unusual Leptospira, Serotype illini (a New Serotype)

During the course of a periodic epidemiological survey for leptospirosis of a herd of bulls at the University of Illinois Agricultural Research Center, Dixon Springs, a new leptospiral strain was isolated from the urine of a clinically healthy Hereford bull, no. 3055. The strain was found to be antigenically unrelated to known pathogenic (Leptospira interrogans) and “saprophytic” (Leptospira bilflexa) serotypes. Phenotypically, it most closely resembled L. biflexa strains; however, in view of the reported distinct genetic characteristics of strain 3055, its species classification is not recommended at this time.