Departament de Medicina i Cirurgia Animals, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Cryobiology. 2011 Dec;63(3):240-4. doi: 10.1016/j.cryobiol.2011.09.002. Epub 2011 Sep 22.
This study examines the effectiveness of the cryotop vitrification method for the cryopreservation of goat blastocysts. To determine the effects of embryo development stage and donor age on in vitro survival rates, good-quality blastocysts from adult and prepubertal goats were sorted into non-expanded, expanded, hatching and completely hatched. In vitro produced (IVP) blastocysts were derived from prepubertal goat oocytes by slicing of ovaries from slaughtered animals while adult goat oocytes were collected by the laparoscopic ovum pick up (LOPU) method. Blastocysts were vitrified/warmed using the cryotop technique. Survival rates were determined in terms of blastocoele re-expansion at 3 and 20 h post-warming. For prepubertal goats, survival rates at 3h post-warming were significantly higher when expanded blastocysts (78.3%) were vitrified/warmed compared to hatched blastocysts (57.4%), whereas non-expanded (62.5%) or hatching blastocysts (71.4%) showed similar rates. For adult goats, survival rates were significantly higher after warming in expanded (36.4%), hatching (75%) or hatched (50%) blastocysts when compared to non-expanded (0%) blastocysts. When survival rates were assessed at 20 h post-warming, no differences were observed when we compared non-expanded (45.8%), expanded (56.5%), hatching (64.3%) and hatched (50.5%) blastocysts from prepubertal goats; and for blastocysts from adult goats, survival rates were only significantly lower for the non-expanded stage (0%) compared to the other stages. For adult versus prepubertal blastocysts at the same developmental stage, our data indicate significantly higher survival rates at 3 h post-warming for non-expanded and expanded blastocysts from prepubertal goats over their counterparts from adult goats. At 20 h post warming, survival rates were only higher for non-expanded blastocysts from prepubertal goats versus adult goats. Collectively, our data reveal that blastocysts produced in vitro from prepubertal goats return similar survival rates regardless of their development stage, whereas blastocysts derived from adult goats are best for vitrification at the expanded, hatching or hatched stage.
本研究探讨了 cryotop 玻璃化法在山羊囊胚冷冻保存中的效果。为了确定胚胎发育阶段和供体年龄对体外存活率的影响，将来自成年和青春期前山羊的优质囊胚分为非扩张、扩张、孵化和完全孵化。体外生产（IVP）的囊胚是通过从屠宰动物的卵巢切片获得的青春期前山羊卵母细胞产生的，而成年山羊卵母细胞是通过腹腔镜卵母细胞采集（LOPU）方法获得的。囊胚采用 cryotop 技术进行玻璃化/复温。以囊胚腔在复温后 3 和 20 小时的再扩张来确定存活率。对于青春期前的山羊，当扩张囊胚（78.3%）进行玻璃化/复温时，3 小时后的存活率明显高于孵化囊胚（57.4%），而非扩张囊胚（62.5%）或孵化囊胚（71.4%）显示出相似的存活率。对于成年山羊，与非扩张囊胚（0%）相比，扩张囊胚（36.4%）、孵化囊胚（75%）或孵化囊胚（50%）的存活率在复温后 3 小时显著更高。当在复温后 20 小时评估存活率时，青春期前山羊的非扩张（45.8%）、扩张（56.5%）、孵化（64.3%）和孵化（50.5%）囊胚之间没有差异；对于成年山羊，只有非扩张阶段（0%）的存活率明显低于其他阶段。对于处于相同发育阶段的成年和青春期前的囊胚，我们的数据表明，青春期前山羊的非扩张和扩张囊胚在复温后 3 小时的存活率明显高于成年山羊的对应囊胚。在复温后 20 小时，只有青春期前山羊的非扩张囊胚的存活率高于成年山羊。总的来说，我们的数据表明，无论其发育阶段如何，来自青春期前山羊的体外生产的囊胚的存活率相似，而来自成年山羊的囊胚在扩张、孵化或孵化阶段进行玻璃化的效果最佳。
