The fine structure of the merozoites and gametocytes of Leucocytozoon caulleryi.

The fine structure of the merozoites and gametocytes of Leucocytozoon caulleryi from the peripheral blood of chickens was studied by means of electron microscopy. Merozoites are oval to elongate and are surrounded by a pellicle. They possess a large nucleus, numerous ribosomes, microtubules, a mitochondrion with tubular cristae, a cytostome, an apical complex consisting of three polar rings, electron-dense paired rhoptries, and micronemes. Mature gametocytes are irregular in shape and are surrounded by a three layered pellicle, and contain a large nucleus, mitochondria with tubular cristae, endoplasmic reticulum, numerous ribosomes, food vacuoles, cytostomes, and lipid inclusions. Macrogametocytes are easily distinguished from the microgametocytes by more ribosome concentration and the presence of well developed endoplasmatic reticulum.