Localization of microorganisms within reproductive organs of the piglouse, Haematopinus suis. A, Intraovarian mycetome consists of several mycetocytes containing rod-shaped microorganisms (arrows). The mycetome is located in contact with lateral oviduct cells (lo). Fluorescence microscope, DAPI; scale bar = 10 μm. B, Posterior pole of the oocyte, mycetome located in a depression of the posterior pole of the oocyte (asterisk). Light microscope, methylene blue; scale bar = 10 μm. C, Mycetome microorganisms (asterisks) are located extracellularly, in contact with oocyte microvilli (mv); oocyte (o). TEM; scale bar = 1 μm. D, Mycetome microorganisms visualized in SEM; scale bar = 1 μm. E, Intracellular microorganisms (arrow) within the oocyte cytoplasm. Fluorescence microscope, DAPI; scale bar = 10 μm.