Histological Analysis of Mouse Reproductive Organs

Histological analyses of mouse testis and epididymis were carried out as described previously^{21 (link)}. Briefly, tissues were dissected and fixed in 10% formalin solution. Fixed tissues were then embedded in paraffin, sectioned and H & E stained by the Histopathology laboratory at Michigan State University. H & E staining was examined under a light microscope (Nikon Eclipse E600) by S.G, H.X., and G.I.P who is a certified veterinarian with extensive experience in mouse reproduction research. For the examination of epididymal sperm, cauda epididymides were collected in M2 medium (Sigma-Aldrich, MO, USA) and immediately transferred into HTF medium (Human Tubal Fluid, EMD Millipore, MA, USA) followed by incubating at 37 °C, 5% CO₂ for 1 hour. An aliquot of sperm suspension (10 µl) was fixed and examined under a phase contrast microscope (Nikon Eclipse Ti-U inverted microscope).