A comparison of different vitrification devices and the effect of blastocoele collapse on the cryosurvival of <i>in vitro</i> produced porcine embryos

Abstract

The aim of this study was to determine the optimum conditions for vitrifying in vitro produced day 7 porcine embryos using different vitrification devices and blastocoele collapse methods. Firstly embryos were collapsed by micro-pipetting, needle puncture and sucrose with and without conducting vitrification. In the next experiment, non-collapsed embryos were vitrified in an open device using either superfine open-pulled straws (SOPS) or the CryoLoopTM system, or vitrified in a closed device using either the CryoTipTM or Cryo BioTM’s high security vitrification system (HSV). The post-thaw survival of embryos vitrified in the open devices did not differ significantly (SOPS: 37.3%; CryoLoopTM: 37.3%) nor did the post-thaw survival of embryos vitrified in the closed devices (CryoTip™: 38.5%; HSV: 42.5%). The re-expansion rate of embryos that were collapsed via micro-pipetting (76.0%) did not differ from those that were punctured (75.0%) or collapsed via sucrose (79.6%) when vitrification was not performed. However, embryos collapsed via sucrose solutions (24.5%) and needle puncture (16.0%) prior to vitrification were significantly less likely to survive vitrification than the control (non-collapsed) embryos (53.6%, P < 0.05). The findings show that both open and closed vitrification devices were equally effective for the vitrification of porcine blastocysts. Collapsing blastocysts prior to vitrification did not improve survival, which is inconsistent with the findings of studies in other species. This may be due to the extremely sensitive nature of porcine embryos, and/or the invasiveness of the collapsing procedures.

Effect of different penetrating and non‐penetrating cryoprotectants and media temperature on the cryosurvival of vitrified in vitro produced porcine blastocysts

“…In clinical settings, commercially available media are usually used to vitrify embryos because they are considered to be more stringently tested, reliable, and convenient than media prepared in‐house. Consistent with our previous findings (Bartolac et al., ), we showed that the post‐warm survival rate of day 7 IVP porcine embryos vitrified using Vitrolife media was similar to that obtained using our standard in‐house media. A previous comparison of in‐house and commercial media also found they were equally effective for vitrifying pronuclear stage human embryos (Alcolak et al., ).…”

“…Consistent with our previous findings (Bartolac et al, 2015), we showed that the post-warm survival rate of day 7 IVP porcine embryos vitrified using Vitrolife media was similar to that obtained using our standard in-house media. A previous comparison of inhouse and commercial media also found they were equally effective for vitrifying pronuclear stage human embryos (Alcolak et al, 2011).…”

“…The sucrose concentration in vitrification solution of the high EG protocol was nearly eight times that of the control which could have also had a negative impact on survival. The detrimental impact high sucrose concentrations have on survival was also highlighted previously by Bartolac, Lowe, Koustas, Sjöblom, and Grupen () who showed a decrease in post‐warm survival when blastocysts were exposed to high concentrations of sucrose prior to vitrification. Although there are a number of variables in both vitrification solutions directly compared here, it is suspected the high concentration of EG may have exerted a greater toxic effect or provided a reduced cryoprotective effect than EG + DMSO combined.…”

Vitrification of equine expanded blastocysts following puncture with or without aspiration of the blastocoele fluid

“…Furthermore, forced collapse of the blastocoele cavity in both in vitro and in vivo generated bovine blastocysts prior to cryopreservation increased the number of live offspring born to recipients [25]. On the other hand, blastocoele collapse of in vitro produced porcine embryos prior to vitrification did not improve survival [26].…”

Perbandingan Viabilitas Oosit Domba Pasca Vitrifikasi dengan Menggunakan Hemistraw dan Cryotop

“…Salah satu upaya untuk menyeimbangkan laju pendinginan adalah dengan menggunakan carrier yang mampu memperkecil volume krioprotektan yang digunakan. Beberapa jenis carrier yang telah digunakan untuk vitrifikasi oosit adalah cryoloop, cryotop, fibreplug, electron microscop grid, dan lain-lain (Bartolac et al, 2015) Cryotop digunakan sebagai carrier untuk vitrifikasi maupun slow freezing (pembekuan lambat) baik pada oosit maupun pada embrio (Lin et al, 2010). Cryotop kit merupakan carrier dengan sistem tertutup sehingga mampu melindungi secara optimal dari kontaminasi maupun kerusakan secara fisik.…”