Evaluation of the Rapid Strep System for Identification of Gram-Positive, Catalase-Negative Cocci Isolated from Bovine Intramammary Infections

The Rapid Strep system (Analytab Products, Plainview, NY) was used to identify 199 gram-positive, catalase-negative cocci isolated from bovine intramammary infections. The system accurately identified 88.4% of isolates. The system identified 100% of 46 Streptococcus agalactiae, 100% of 48 Streptococcus dysgalactiae, 54.5% of 11 Streptococcus equinus, and 96.2% of 53 Streptococcus uberis isolates. Enterococcus spp. were identified correctly 83.3% of the time. One of 4 Streptococcus saccharolyticus strains was identified as Streptococcus bovis, the previous classification for this organism, and 8 Streptococcus equi ssp. equi strains were misidentified as Streptococcus dysgalactiae. The Rapid Strep system was determined to be an acceptable alternative to conventional methods for identification of gram-positive, catalase-negative cocci isolated from bovine intramammary infections.