Piglets produced by transfer of embryos obtained by in vitro fertilization of oocytes matured in vitro with thymosin: A case report

Abstract

The aim of the study was to examine the in vivo viability of in vitro-produced (IVP) porcine embryos obtained from oocytes matured with thymosin. The research material for this study consisted of immature pig oocytes obtained from ovaries after slaughter and ejaculated semen obtained from one boar. The immature oocytes were cultured in vitro until the metaphase II stage in a medium supplemented with thymosin (TMS). The presumptive zygotes obtained were cultured in vitro for 4-40 hours. The presumptive zygotes and 2-4-cell embryos were evaluated in vivo after transferring them to synchronized recipients. After the transfer of embryos from the experimental group into 2 recipients (50 embryos into each gilt) and the transfer of 50 embryos from the control group into 1 recipient, both gilts that had received embryos obtained by in vitro fertilization of oocytes matured with TMS became pregnant and delivered a total of 16 live piglets. After the transfer of embryos from the control group, no pregnancy was achieved. In conclusion, the results of our preliminary study suggest that the maturation of pig oocytes with thymosin supports the in vivo survival of in vitro produced embryos. It is important to note, that this was the first birth of piglets obtained after transfer of IVP embryos in Poland.

Effect of thymosin β on maturation of pig oocytes and quality of <i>in vitro</i> produced embryos

“…Therefore, TMS supplementation into maturation medium had a positive effect on the quality of obtained blastocysts by limiting the occurrence of apoptosis. In our other studies, we demonstrated that in vivo survivability evaluation of embryos obtained from fertilized oocytes matured with TMS resulted in pregnancy in two recipients and the subsequent birth of 16 live piglets (Poniedziałek-Kempny et al, 2020).…”

“…Culture was carried out at 39 °C, 5% CO 2 and maximum humidity. The maturation medium was described in detail in previous study (Poniedziałek-Kempny et al, 2020). The oocytes were randomly divided into 3 groups: A.…”

“…Oocytes and spermatozoa were co-incubated for 4 h in humidified atmosphere containing 5% CO 2 in the air, at 39 °C. The IVF procedure was described in details by Poniedziałek-Kempny et al (2020). The IVF experiments were performed in 6 repetitions.…”

“…Presumptive zygotes were cultured in North Carolina State University-23 (NCSU-23) medium (Petters and Wells, 1993) that was supplemented with 4 mg/ml BSA. The culture procedure was demonstrated in a previous study by Poniedziałek-Kempny et al (2020). The number of presumptive zygotes, morulae and expanded blastocysts was evaluated.…”

Expression and Impact of Vaspin on In Vitro Oocyte Maturation through MAP3/1 and PRKAA1 Signalling Pathways

“…As we anticipated, we showed the stimulatory effect of vaspin (1 ng/mL) on nuclear oocyte maturation. The total time to undergo metaphase-II for porcine oocytes cultured in vitro is 44 h [32]. In our experiments, we checked the progress in oocyte maturation by counting the percentage of oocytes first in metaphase-I after 22 h of culture (percentage of oocytes in metaphase-I) and then at metaphase-II after 44 h. The positive effect of vaspin on oocyte maturation was confirmed by increases in P4 levels in the culture medium after 22 and 44 h of culture.…”