Sarcocystis muris--a rare case in laboratory mice
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1Institut für Experimentelle Pathologie, Medizinische Hochschule Hannover, Germany.
Abstract:
In a lifespan transgeneration study under standard laboratory conditions using a total of 4682 CBA/J mice, unusual intramuscular inclusions were found in the diaphragm, heart and skeletal muscle of one mouse using light microscopy. Located within the myocytes, they caused no visible tissue reaction. Cross-sections of these spherical and cystic lesions showed numerous banana-shaped structures, identified as permanent parasitic bradyzoites, which permitted these infections to be diagnosed microscopically as sarcocystosis.
Insights
Unusual intramuscular inclusions in mice were identified as parasitic bradyzoites, indicating sarcocystosis. This microscopic finding occurred in a lifespan transgeneration study involving 4682 mice.
Area of Science:
- Veterinary Pathology
- Parasitology
- Mouse Models
Background:
- Lifespan transgeneration studies are crucial for understanding long-term health effects.
- Intramuscular inclusions can indicate various pathological conditions in animal models.
- Sarcocystosis is a parasitic disease caused by protozoa of the genus Sarcocystis.
Purpose of the Study:
- To identify and characterize unusual intramuscular inclusions found in a mouse from a lifespan transgeneration study.
- To determine the etiological agent responsible for the observed microscopic lesions.
Main Methods:
- Microscopic examination of muscle tissue (diaphragm, heart, skeletal muscle) from CBA/J mice.
- Analysis of intramuscular inclusions using light microscopy.
- Identification of parasitic structures within the lesions.
Main Results:
- Unusual intramuscular inclusions were observed in the diaphragm, heart, and skeletal muscle of one mouse.
- The inclusions contained numerous banana-shaped structures identified as permanent parasitic bradyzoites.
- These findings are indicative of sarcocystosis, a parasitic infection.
Conclusions:
- The identified intramuscular inclusions represent sarcocystosis in a mouse model.
- Microscopic diagnosis of sarcocystosis is feasible through the identification of bradyzoites.
- This finding highlights the importance of detailed histopathological examination in long-term animal studies.
