THE INTESTINAL FLORA IN MOUSE TYPHOID INFECTION

Area of Science:

• Microbiology
• Animal Science
• Bacteriology

Background:

• Understanding the normal gut microbiota is crucial for studying host-pathogen interactions.
• Laboratory mice are common models for infectious disease research.
• Diet can influence the composition of the gut microbiome.

Purpose of the Study:

• To characterize the normal flora of laboratory mice at The Rockefeller Institute.
• To investigate the impact of mouse typhoid bacilli infection on the gut microbiota.
• To determine if dietary changes affect gut flora composition and susceptibility to infection.

Main Methods:

• Microbiological analysis of fecal samples from mice on a bread and milk diet.
• Artificial infection of mice with mouse typhoid bacilli (Bacillus pestis cavice).
• Comparison of gut flora in infected and non-infected mice, and in mice with different diets.

Main Results:

• Bacillus acidophilus and Bacillus bifidus were the predominant bacteria, outnumbering other groups significantly.
• Gut flora composition remained consistent despite artificial infection with mouse typhoid bacilli.
• Mice on a meat diet did not show altered susceptibility to mouse typhoid compared to those on a bread and milk diet.

Conclusions:

• The normal gut flora of these laboratory mice is robust and not significantly altered by mouse typhoid infection.
• Dietary variations did not influence the susceptibility of mice to mouse typhoid.
• The study provides baseline data on mouse gut microbiota in the context of infectious disease research.