Abstract: Objective To investigate the death process of the granulocytes in oviduct after ovulation.Methods Oviducts were observed at 5, 8 and 12 h after mating with histology, TUNELstaining, immunohistochemistry, and transmission electron microscopy.Results All oviduct ampullae at 5 h after mating contained oocytes surrounded with numerous granulocytes, and the majority of granulocytes disappeared from the ampulle at 12 h.At 5 h after mating, approximately 5% of granulocytes were TUNELstaining positive and, at 8 h, 30% were TUNELstaining positive.Ultrastructurelly, there were nuclear changes characterized mainly by compaction and margination of heterochromatin.These were designated as signs of classical apoptosis.In addition, some granulocytes, approximately 2% at 5 h and 13% at 8 h after mating, showed mitochondrial swelling and disruption of cellular, nuclear and the other organelle membranes.These were designated as typical signs of necrotic cell death.Among the granulocytes, there were F4/80 positive cells that contained TUNELstaining positive bodies.Conclusion Granulocytes died and disappeared rapidly from oviduct ampullas through two different death processes after ovulation, apoptosis and necrosis, and macrophages may be involved in apoptotic cell disposal pathways.

Key words: oviduct ampulla, granulosa cells, ovulation, apoptosis, mouse