The hearts of 893 sows from Iowa killed for food between January 1990
and February 1992 were examined for Sarcocystis bradyzoites by the dig
estion technique. Bradyzoites were found in 163 (18.2%) hearts. Sectio
ns of formalin-fixed tissues from 28 hearts with demonstrable bradyzoi
tes were examined for sarcocysts. Sarcocystis miescheriana sarcocysts
were found in six pigs. The prevalence of Sarcocystis was apparently n
ot affected by season.