Sarcocystis spp. in birds of the order Anseriformes.

Having studied 342 birds of 20 species of the order Anseriformes, we found Sarcocystis cysts in 100 individuals (29.2+/-2.5%) belonging to 15 species. One macrocyst and four microcysts types have been determined. By means of light microscopy, the morphology of cyst walls and merozoites have been examined and morphometric data are presented. According to morphological features, macrocysts correspond to the S. rileyi species.