Effects of glyphosate-based herbicides on survival, development, growth and sex ratios of wood frogs (Lithobates sylvaticus) tadpoles. I: chronic laboratory exposures to VisionMax®.

摘要: Abstract The purpose of this study was to determine if chronic exposure the glyphosate-based herbicide VisionMax® affects survival, development, growth, sex ratios and expression specific genes involved in metamorphosis wood frog tadpoles (Lithobates sylvaticus). We hypothesized that will affect developmental rates by disrupting hormone pathways, and/or gonadal morphology. Tadpoles were chronically exposed laboratory from Gosner stage 25 42 four different concentrations (ranging 0.021 2.9 mg acid equivalents/L). Chronic exposures had direct effects on L. sylvaticus decreasing development rates, however, there a decrease survival only group highest dose (2.9 mg a.e./L; approximately 96% control 77% treatment group). There number reaching metamorphic climax, 78% 42% (2.9 mg a.e./L) group, 7-day delay reach climax same group. No or morphology detected any tested. Gene analyses brain tail tissues demonstrated alters key development. Results showed significant interaction (two-way ANOVA, P