[Nosema sp. in white rats]

Area of Science:

• Veterinary Parasitology
• Microbiology
• Mammalian Disease Models

Context:

• Microsporidians are opportunistic pathogens that can infect a wide range of hosts, including mammals.
• Diagnosis of microsporidian infections in mammals can be challenging due to low parasite loads and varied clinical presentations.
• Nosema species are among the most common microsporidian genera, with some species known to infect rodents.

Purpose:

• To investigate the infectivity and transmissibility of Nosema sp. in a murine model.
• To characterize the morphology and size of Nosema sp. spores found in infected mice.
• To evaluate the feasibility of using a brain emulsion for Nosema sp. infection and subsequent diagnosis.

Summary:

• Intraperitoneal inoculation of mice with a 30% brain emulsion from infected white mice or newborn rats resulted in the detection of Nosema sp. spores within 14 days.
• The identified Nosema sp. spores measured approximately 5.37 x 3.04 micrometers.
• Attempts to passage the organism to new mice using suspensions from the brains and internal organs of infected animals were unsuccessful, suggesting limited transmissibility via this route.

Impact:

• This study highlights the potential for Nosema sp. infection in murine models but also underscores the difficulties in experimental transmission.
• The findings suggest that current diagnostic methods or experimental protocols may not be sufficient for detecting or culturing Nosema sp. from all infected tissues.
• Further research is needed to optimize diagnostic techniques and understand the transmission dynamics of microsporidians in mammalian hosts.