Quantification of reduced IMI intermediates (DNI and IMI-urea) in media cultured with and without antral follicles. Media were treated with DMSO or IMI (0.2–200 µg/ml) for 48 (A) and 96 (B) hours. The graphs indicate means ± SEMs from 5 to 7 separate cultures (8–12 follicles per treatment per culture). Note: IMI-urea was not present in media cultured without follicles. Abbreviations: DMSO, dimethyl sulfoxide; DNI, desnitro-imidacloprid; IMI, imidacloprid.