Importance of broth-enrichment culture in equine endometritis diagnosis

The objective of this study was to investigate the diagnostic accuracy of the standard microbiological protocol to assure the evaluation of bacterial endometritis in the equine clinical practice. Four hundred fifty-two equine uterine swabs were seeded on different types of agar plates and then in a broth-enrichment (Brain Heart Infusion Broth) before plating by using the same media the day after. The prevalence of positivity was 33.7% following direct plating and 66.3% following use of added enrichment-broth phase before seeding on solid media. Furthermore, the prevalence of isolated bacteria included E. coli (29.7%) and Streptococcus equi subsp. zooepidemicus (15.2%), both frequently associated with equine endometritis. Our results indicate that the addition enrichment-broth culture significantly increases the rate of positivity for the detection of bacteria in equine uterine swabs compared to the direct plating of samples alone. Thus, this diagnostic technique may be recommended to increase the sensitivity of bacteriological analysis in mares with endometritis.