Evaluation of Chromocult® enterococci agar for the isolation and selective enumeration of Enterococcus spp. in broilers
Article first published online: 9 JUN 2005
Letters in Applied Microbiology
Volume 41, Issue 2, pages 153–156, August 2005
How to Cite
Miranda, J.M., Franco, C.M., Vázquez, B.I., Fente, C.A., Barros-Velázquez, J. and Cepeda, A. (2005), Evaluation of Chromocult® enterococci agar for the isolation and selective enumeration of Enterococcus spp. in broilers. Letters in Applied Microbiology, 41: 153–156. doi: 10.1111/j.1472-765X.2005.01728.x
- Issue published online: 23 JUN 2005
- Article first published online: 9 JUN 2005
- 2005/0063: received 21 January 2005, revised 15 March 2005 and accepted 17 March 2005
- chromogenic media;
Aims: To investigate the productivity and specificity of a new chromogenic enterococci selective medium (Chromocult® enterococci agar) recently developed by Merck.
Methods and Results: The study was carried out comparing Chromocult® enterococci agar with MRS agar (Merck), a basal lactic acid bacteria medium in current use. A total of 216 faecal samples from poultry were collected and enterococci populations were counted. Likewise, 100 randomly selected strains were identified for each medium. The differences found between the two media were analysed and discussed.
Conclusions: A good sensitivity of 98% was obtained for Chromocult® agar and all false-positive isolates obtained were identified as Leuconostoc spp. However significant differences (P < 0·01) were obtained between the enterococci species isolation rates identified from these two media, suggesting the poor growth of some species in Chromocult® enterococci agar. Viable counts of Enterococcus spp. obtained with MRS agar were significantly higher than those obtained with Chromocult® enterococci agar.
Significance and Impact of the Study: The use of chromogenic media for microbiological analysis is increasing. Independent studies are important to evaluate newly developed chromogenic media.