Effect of Roundup on the Release of Reproductive Hormones in Rough Shiner (Notropis baileyi)

Abstract

Roundup is the most used herbicide across the world, with over a billion kgs applied in the US since its introduction in 1974. Long thought to be harmless to non-target species, recent studies have called this supposition into question. Aquatic environments are particularly susceptible, as Roundup binds to the soil and can be washed into the water spiking concentrations for several days. Our research focused on the effect of Roundup on fish reproduction, looking at three common reproductive hormones (prostaglandin-F2a, 11-ketotestosterone, and estradiol) produced by leuciscids. Our research found significant impacts to fishes’ ability to detect and react to the reproductive signal prostaglandin-F2a, which is essential for ensuring simultaneous breeding. After fish were exposed to Roundup for 3 days, they released significantly less of all three reproductive hormones studied in this experiment, with levels of prostaglandin-F2a and 11-ketotestoterone being too low to detect.