Amylopectin, the Storage Polysaccharide of the Coccidia Eimeria brunetti and E. tenella

Electron micrographs are presented showing the distribution of polysaccharide in the sporozoite, sporocyst residual body, and merozoite of Eimeria tenella. Polysaccharide in situ stains brown with iodine and magenta following PAS treatment. Polysaccharide has been isolated from oocysts of E. brunetti and E. tenella and from sporozoites and merozoites of E. tenella by the use of alkali. Isolated polysaccharide from these sources stains purple with iodine, but a brown color is obtained in the presence of protein. Chemical and enzymic investigation of the isolated polysaccharides have shown them to be typical amylopectins with chain lengths of about 20 glucose residues.