Rapid identification of the animal pathogens Streptococcus uberis and Arcanobacterium pyogenes by fluorescence in situ hybridization (FISH)

Fluorescence in situ hybridization (FISH) has been reported to be an easy and rapid identification method for many human pathogens, but applications for common veterinary pathogens are lacking. Gene probes for FISH of the animal pathogens Streptococcus uberis and Arcanobacterium pyogenes were designed to provide probes for a specific identification of these bacteria from cultures. Specific FISH probes for these species have so far not been published. Both probes recognized all isolates of the target species correctly. With the S. uberis probe SUB 196 no false-positive results were obtained for reference strains as well as for clinical isolates. Probe APYO 183 for A. pyogenes produced false-positive reactions with so far rarely described Arcanobacterium species from animals at standard hybridization conditions. In order to avoid any incorrect classifications of microorganisms as A. pyogenes, two non-labelled competitor probes were designed and successfully evaluated.