Objective—To determine apparent seroprevalence of
antibodies against Sarcocystis neurona in a population
of domestic cats previously tested for antibodies
against Toxoplasma gondii.
Sample Population—Serum from 196 domestic cats.
Procedure—Banked serum samples submitted to
the Michigan State University Animal Health
Diagnostic Laboratory for T gondii diagnostic testing
were tested for antibodies against S neurona by use
of an indirect fluorescent antibody (IFA) test and a
western blot test. Submission records were analyzed
to determine descriptive statistics and test for associations
between positive results of a test for S neurona
and other variables in the data set.
Results—10 of 196 (5%) samples yielded positive
results for antibodies against S neurona by use of
western blot analysis, whereas 27 samples yielded
positive results by use of the IFA. No association was
found between S neurona western blot test results
and T gondii test results, age, sex, or the reason for T
gondii testing. The S neurona IFA titer was positively
and significantly associated with positive results of
western blot analysis.
Conclusions and Clinical Relevance—Domestic
cats are not likely to play a substantial role as intermediate
hosts in the natural life cycle of S neurona.
Results indicate that natural infection of domestic
cats may occur, and small animal practitioners should
be aware of this fact when evaluating cats with neurologic
disease. The S neurona IFA test had lower
specificity than western blot analysis. (J Am Vet Med