Observation on the morphology of contagious equine metritis bacterial colonies isolated from infected pony mares.

The research article studies the different morphological variations in colonies of contagious equine metritis (CEM) bacteria isolated from infected pony mares, and how these colonies differ when grown on different agar mediums.

Research Objective and Process

• The study aimed at observing and identifying the morphological differences in the colonies of a streptomycin-resistant strain of contagious equine metritis bacteria found in infected pony mares.
• Uterine or cervical specimens from infected mares were collected and bacteria were isolated on two types of agar plates: Eugon chocolate agar and tryptose chocolate agar.
• The morphological changes in the bacteria colonies were monitored over an incubation period of 10 to 15 days.

Observations and Results

• In colonies grown on Eugon chocolate agar plates, three different types of colonies were identified: smooth colony, sandy colony with rings, and colony with blebs.
• On tryptose chocolate agar plates, only one type of colony was identified, a round smooth convex colony.
• It was noted that these different morphological types were seen only after 10 to 15 days of incubation.

Microscopic Analysis

• Further analysis of the colonies was carried out using scanning electron microscopy.
• This revealed that colonies consisted of cocci (spherical bacteria), coccobacilli (partly spherical and partly rod-shaped), and bacilli (rod-shaped bacteria).

Noteworthy Conclusions

• Interestingly, the researchers found that only one type of colony was isolated from any single mare, underscoring the specificity of bacterial infection and growth.
• This thorough observation of colony morphology can lead to a better understanding of bacterial growth and behavior, which can further aid in the effective treatment and control of contagious equine metritis.