Sperm invasion of the oviducal mucosa, fibroblastic phagocytosis and endometrial sloughing in the Japanese greater horseshoe bat, Rhinolophus ferrumequinum nippon.

In the Japanese greater horseshoe bat, Rhinolophus ferrumequinum nippon, a vast number of spermatozoa invade the oviducal epithelial cells of the caudal isthmus and become concentrated in the endometrial lamina propria of the bicornuate horns. They are subsequently phagocytised and digested by fibroblasts. Then, finally, they become deposited in the uterine lumen together with a large quantity of secretory material from the endometrial connective tissue which, prior to this event, undergoes a massive infiltration by polymorphonuclear leucocytes.