University of Missouri researchers at the College of Agriculture, Food and Natural Resources have found that zinc plays a key role in promoting fertility in males. Peter Sutovsky, Professor of Animal Science, explains how his lab’s discovery, linking zinc directly with fertility, can improve in vitro fertilization and artificial insemination in livestock. He says the discovery can improve human infertility diagnostics and therapies. The study was set in motion by a new biological phenomenon called “zinc spark” on the oocyte (egg or female) side, occurring post-fertilization. However, what zinc does on the male side within sperm before it meets the egg hasn’t been described, so the researchers set out to complete the biological story.