The pathological changes caused by Eimeria falciformis var pragensis in mice

Area of Science:

• Veterinary Parasitology
• Immunology
• Gastroenterology

Background:

• Eimeria falciformis var pragensis is a protozoan parasite known to infect rodents.
• Understanding the host-parasite interactions and pathogenesis of coccidiosis is crucial for disease management.

Purpose of the Study:

• To characterize the dose-dependent effects of Eimeria falciformis var pragensis infection on Swiss white mice.
• To detail the pathological changes and inflammatory responses in the murine intestine following infection.

Main Methods:

• Swiss white mice were orally infected with varying doses of Eimeria falciformis var pragensis oocysts (500 to 20,000).
• Clinical signs, mortality, and gross pathological findings were monitored.
• Histopathological analysis of the large intestine was performed at different time points postinfection.

Main Results:

• Clinical signs and mortality were dose-dependent, with the highest mortality (31%) observed at 20,000 oocysts.
• Pathological findings included cryptal and absorptive epithelial cell destruction, submucosal edema, and inflammatory cell infiltration, primarily in the large intestine.
• Necrosis and ulceration were observed, followed by crypt hyperplasia and mucosal repair. Granulomatous colitis and lymphoid hyperplasia were also noted.

Conclusions:

• Eimeria falciformis var pragensis infection induces significant enteric pathology in mice, with severity directly related to the oocyst dose.
• The inflammatory response involves neutrophils and mononuclear cells, leading to tissue damage, repair, and long-term changes like granulomatous colitis.