Mouse model for central nervous system Neospora caninum infections

Area of Science:

• Veterinary Parasitology
• Immunology
• Infectious Diseases

Background:

• Neospora caninum causes significant disease in dogs and livestock.
• Current rodent models of neosporosis require immunosuppression with methylprednisolone acetate (MPA).

Purpose of the Study:

• To develop a novel inbred BALB/c mouse model for Neospora caninum infection without MPA treatment.
• To evaluate the susceptibility of BALB/c and HSD:ICR mice to different N. caninum strains.

Main Methods:

• Subcutaneous inoculation of inbred BALB/c mice and HSD:ICR mice with N. caninum tachyzoites (NC-1 and NC-3 strains).
• Monitoring of clinical signs, mortality, and brain lesions in inoculated mice.
• Comparison of infection outcomes between mouse strains and N. caninum strains.

Main Results:

• BALB/c mice inoculated with the NC-1 strain exhibited mortality and developed central nervous system neosporosis without MPA treatment.
• BALB/c mice inoculated with the NC-3 strain or HSD:ICR mice with either strain did not develop clinical neosporosis or die.
• Significantly more BALB/c mice infected with the NC-1 strain showed brain lesions compared to other inoculated groups.

Conclusions:

• The inbred BALB/c mouse model is susceptible to N. caninum (NC-1 strain) induced central nervous system neosporosis without immunosuppression.
• This model offers a valuable tool for studying neosporosis pathogenesis and evaluating therapeutic strategies.
• Strain and parasite isolate selection are critical factors in establishing experimental neosporosis models.