REPRODUCTIVE CAPACITY OF THE NUCLEUS OF THE MALE GAMETE AFTER COMPLETION OF MEIOSIS

Purpose: Our purpose was to investigate the possibility of achieving f ertilization and subsequent nor mal embryonic development by injecting round spermatid nuclei into rabbit oocytes. Results: Two- to four-cel l-stage embryos developed after round spermatid nuclear injections int o rabbit ooplasma could further develop in vitro up to the expanding b lastocyst stage or in vivo lip to complete gestation. Conclusion: The current findings show that the haploid set of chromosomes of round spe rmatid can pair with the chromosomes of the ootid to participate in co mplete fertilization and subsequent embryonic and fetal development. I n addition, we suggest that postmeiotic modifications of the round spe rmatid are not required for the pairing of male gamete chromosomes wit h those of the ootid.