An Immunolabelling Technique to Track Sperm from Different Mates in the Female Reproductive Organs of Terrestrial Gastropods

Abstract

ABSTRACT The mechanisms of sperm transfer, storage, utilization and digestion are crucial for understanding processes of postcopulatory sexual selection. Previous studies analysing postcopulatory processes have generally focused only on the ultimate outcome of the interactions between male and female sexual selection (paternity patterns). For a mechanistic understanding of the fate of received sperm and the involved patterns of postcopulatory sexual selection new techniques are required. Here we present an improved immunolabelling technique to track the fate of 5-bromo-2′-deoxyuridine (BrdU)-labelled sperm in the female reproductive organs of gastropods. The technique was tested in individuals of the simultaneously hermaphroditic land snail Arianta arbustorum (Linnaeus, 1758). We determined the percentage of labelled sperm in spermato-phores delivered and assessed the reliability of detecting labelled sperm in the spermatheca (sperm storage organ) and bursa copulatrix (sperm digestion organ) of the recipi...