Batchwise assessment of porcine embryos for cryotolerance
Batchwise assessment of porcine embryos for cryotolerance
复制标题
DOI：
10.1016/j.theriogenology.2006.08.008
复制
发表时间：
2007-01-15
期刊：
影响因子：
2.8
通讯作者：
Nagai, Takashi
中科院分区：
文献类型：
--
作者：
Fujino, Yukihiro;Kikuchi, Kazuhiro;Nagai, Takashi
猪胚胎在缓慢冷冻和解冻后的活力或发育能力根据胚胎阶段或批次而不同，批次定义为一次从一个供体获得的一组胚胎。以2个扩张囊胚为样本，对猪囊胚进行批量冷冻，并对其耐冷性进行评价，以预测同一批囊胚在不同发育阶段的发育潜力。将来自同一批次的已分别冷冻的两个EB解冻并在体外培养48 h，以检查它们在体外发育至孵化囊胚期的能力。此后，根据两种EB的活力将每批分配为A、B或C级，即，100%活力（2/2：孵化囊胚数量/培养EB数量）为A级; 50%（1/2）为13级; 0%（0/2）为C级。冷冻-解冻和体外培养后EB的活力根据批次而变化，并且较低（31.0 +/-10.2%，平均值+/- S.E.M.; P < 0.01）高于未冷冻对照组（96.8 +/-2.3%）。冻融孵化的囊胚（HB）的活力没有不同的分级批次，但囊胚直径下降（从409 μ m至326 μ m）的批次等级下降（从A到C）。当同一批次的EB和HB同时转移给受体（平均每只受体11.7 EB和16.0 HB）时，受体的妊娠率和分娩率随着批次等级的降低而降低（从77.8%降至0%），获得的仔猪数也随之降低（从15.3降至0）。然而，当不仅移植来自B或C级批次的冻融EB，而且移植桑椹胚至早期囊胚阶段的4个辅助胚胎（预期支持妊娠）时，来自B级批次的EB（16.0）产生的仔猪数量高于来自C级批次的EB（0.0）。当转移冻融HB和辅助胚胎时，来自B级批次的HB产生的小猪数量（12.7）高于来自C级批次的HB产生的小猪数量（1.9）。猪囊胚慢速冷冻后，其存活至仔猪阶段的比率逐批不同，冷冻和解冻后样品EB的体外活力评估可能有助于评估来自同一批次的处于不同阶段的其他囊胚的冷冻后和解冻后发育潜力。(c)2006年爱思唯尔公司All rights reserved.
The viability or developmental ability of porcine embryos after slow-freezing and thawing differs depending on the embryonic stage or the batch, which is defined as a group of embryos obtained from one donor at one time. We froze porcine blastocysts in batches and assessed their cryotolerance by using two expanded blastocysts (EBs) as samples to predict the developmental potential of other blastocysts from the same batch at different stages. Two EBs from the same batch that had been separately frozen were thawed and cultured in vitro for 48 h to examine their in vitro ability to develop to the hatched blastocyst stage. Thereafter, each batch was assigned to Grade A, B, or C according to the viability of the two EBs, i.e., 100% viability (2/2: number of hatched blastocysts/number of cultured EBs) was Grade A; 50% (1/2) was Grade 13; and 0% (0/2) was Grade C. The viability of EBs after freeze-thawing and in vitro culture varied depending on the batch and was lower (31.0 +/- 10.2%, mean +/- S.E.M.; P < 0.01) than that of unfrozen controls (96.8 +/- 2.3%). The viability of frozen-thawed hatched blastocysts (HBs) did not differ among the graded batches, but the blastocyst diameter decreased (from 409 to 326 mu m) as the batch grade decreased (from A to C). When both EBs and HBs from batches of the same grade were transferred to recipients (average 11.7 EBs and 16.0 HBs per recipient), the rate of pregnancy and farrowing in recipients decreased (from 77.8% to 0%) and the number of piglets obtained decreased (from 15.3 to 0) as the batch grade decreased. However, when not only frozen-thawed EBs from Grade B or C batches, but also four helper embryos at the morula to early blastocyst stage (which were expected to support the pregnancy) were transferred, the number of piglets generated was higher from EBs from Grade B batches (16.0) than from EBs from Grade C batches (0.0). When frozen-thawed HBs and helper embryos were transferred, the number of piglets generated was higher from HBs from Grade B batches (12.7) than that from HBs from Grade C batches (1.9). After slow-freezing of porcine blastocysts, their rate of survival to the piglet stage differs batchwise, and in vitro viability assessment of sample EBs after freezing and thawing may help in assessing the post-freezing and post-thawing developmental potential of other blastocysts at different stages from the same batch. (c) 2006 Elsevier Inc. All rights reserved.