Background: It is a common practice to rest vitrified-warmed matured oocytes for 1-3 hours, as a treatment to recover spindle and cytoskeleton, before commencing a further treatment. Vitrified-warmed matured oocytes, however, are very sensitive and may resume meiosis spontaneously during this recommended rest time. Therefore, the aim of this study was to assess spindle and chromosome status as ...

Zeaxanthin is a common carotenoid, which is a powerful antioxidant that protects against damage caused by reactive oxygen species. The aim of the present study was to investigate the effects of zeaxanthin supplementation on in vitro maturation of porcine embryo development. We investigated nuclear maturation, intracellular glutathione (GSH), and reactive oxygen species (ROS) levels during in vi...

Micropsectra sedna (Oliver, 1976) is a parthenogenetic midge from the Canadian Arctic. The parthenogenetic mechanism is apomictic thelytoky, with a restitutional division during oogenesis, as found in other parthenogenetic Chironomidae. It is triploid, with two similar chromosome sets, and the third is relatively dissimilar, pairing little with the diploid set. Two karyotypes were observed: a s...

Background: Cryopreservation of in vitro matured oocytes is a useful technique because the oocytes can be used for some assisted reproductive technologies. On the other hand, the cryopreservation of oocytes is an open problem as a result of their structural sensitivity to the freezing process. The purpose of this study was to evaluate the effect of vitrification on in vitro development of vitri...