Research Note: Preliminary results, first detection of Enterococcus cecorum from environmental samples by streaking on X-Gluc containing selective media

Abstract

The isolation of cultivable E. cecorum from the environment of poultry houses remains a challenge. Environmental samples (dust wipes, equipment swabs, pooled feces) and samples from culled bird vertebras were collected from an infected broiler flock on d 37 posthatching. To isolate the bacterium from the cultivable microbiota, suspensions from the environmental samples were streaked onto a blood agar base medium supplemented with 5-bromo-4-chloro-3-indolyl-beta-D-glucuronic acid cyclohexylammonium salt (X-Gluc), colistin sulfate, and nalidixin. The chromogenic reaction facilitated the isolation of E. cecorum from contaminated surfaces and pooled feces. Isolates from both the environment and vertebras were confirmed using MALDI-TOF and PCR analysis. Colony appearance and antimicrobial susceptibility tests revealed no phenotypic differences among the isolates. It remained unclear whether the isolates originated from the same clone. However, the principle of isolating the pathogen by streaking on a chromogenic agar may motivate researchers to investigate the transmission routes of infectious isolates, potentially leading to the optimization of biosecurity measures.