Figure 1. Effects of different doses of AAI on the porcine oocyte maturation. (A) Representative images of oocyte meiotic progression in control and AAI-exposed oocytes. Cumulus cell expansion of cumulus oocyte complexes (COCs) and polar body extrusion (PBE) of denuded oocytes (DOs) were imaged by the confocal microscope. Scale bar, 360 μm (a, e); 120 μm (b, f); 40 μm (c, g); 40 μm (d, h). (B) The rate of PBE was recorded in control and different concentrations of AAI-exposed groups (10 μM, 25 μM, 50 μM and 100 μM) after culture for 44 h in vitro. Data were presented as mean percentage (mean ± SEM) of at least three independent experiments. *P < 0.05, **P < 0.01, ***P < 0.001.