Parthenogenetic embryos are an ethically acceptable alternative for the derivation of human embryonic stem cells. In this work, we propose a new strategy to produce bovine parthenogenetic embryos inhibiting the emission of the first polar body during in vitro maturation, and allowing the extrusion of the second polar body during oocyte activation. Cytochalasin B, an inhibitor of actin microfilaments, was employed during in vitro maturation to inhibit first polar body emission or during parthenogenetic activation to block second polar body emission. Only one polar body was inhibited in each strategy in order to keep the diploid chromosome set. In experiment 1, the effect of cytochalasin B on in vitro maturation of bovine oocytes was evaluated. Most oocytes... |