PHENOTYPIC AND GENOTYPIC CHARACTERIZATION OF ATYPICAL LACTOCOCCUS-GARVIEAE STRAINS ISOLATED FROM WATER-BUFFALOS WITH SUBCLINICAL MASTITIS AND CONFIRMATION OF LACTOCOCCUS-GARVIEAE AS A SENIOR SUBJECTIVE SYNONYMOF ENTEROCOCCUS-SERIOLICIDA

During a survey of bacterial agents that cause subclinical mastitis in water buffalos, we isolated several strains of gram-positive cocci th at appeared to be enterococci except that they grew very slowly at 45% and grew slowly in broth containing 6.5% NaCl, On the basis of the re sults of conventional physiologic tests, these strains were identified as Enterococcus durans. However, none of the strains reacted with the AccuProbe Enterococcus genetic probe. The whole-cell protein profiles of these organisms were compared with the profiles of Enterococcus an d Lactococcus reference strains, Apart from minor quantitative differe nces, the mastitis isolates had indistinguishable protein profiles tha t were similar to the profiles of the Lactococcus garvieae and Enteroc occus seriolicida type strains, The results of DNA relatedness studies performed by using the hydroxyapatite method at 55 and 70 degrees C i ndicated that all of the mastitis isolates were related to the type st rain of L. garvieae at the species level, despite the fact that they e xhibited several uncommon phenotypic characteristics (growth at 45 deg rees C, growth in broth containing 6.5% NaCl, and failure to produce a cid from mannitol and sucrose), The high levels of DNA relatedness bet ween strains of L, garvieae and E. seriolicida demonstrated that these taxa are members of a single species. Since L. garvieae is a senior s ynonym of E. seriolicida, L, garvieae should be retained as the specie s name and strain ATCC 43921 should remain the type strain of this spe cies.