Cytoplasmic dysmorphisms in metaphase II chimpanzee oocytes

Prior to fertilization by intracytoplasmic sperm injection (ICSI), cytoplasmic organization was evaluated in metaphase II chimpanzee oocytes obtained from stimulated ovaries. The findings demonstrate a high frequency of anomalies that are remarkably similar to the types of cytoplasmic dysmorphisms reported for human oocytes used in IVF. Similar to the human, the occurrence of these anomalies was oocyte- and animal-specific and associated with reduced competence as indicated by embryo development in vitro to the blastocyst stage.