Fig. 1. Extrusion of polar bodies after spawning. Photographs were taken at the indicated times (minutes) after the injection of 1-MA into the body cavity of the recipient animal. (Top panels) Immediately after spawning (35 minutes after the injection of 1-MA into the body cavity), the oocyte was inseminated. The first and second polar bodies (arrowheads: 1stPB and 2ndPB) were formed after the elevation of the fertilization envelope, indicating that they were extruded after fertilization or spawning. (Middle and bottom panels) Oocytes spawned into SW at 95 or 155 minutes after the injection of 1-MA were inseminated. Similarly, polar bodies were extruded after spawning. Scale bar: 50 µm.