PDF(Pubmed)
Abstract：
Epididymal spermatozoa obtained post mortem are considered a valuable source of genetic material which is often irrevocably lost. This makes these gametes constitute a key element in protection and restitution programs. The wisent (Bison bonasus, Linnaeus 1758) is a species that survived in zoos after extinction from its natural habitat. This resulted in a narrowing of the genetic pool of the whole population, which is at present derived from only 12 ancestors. Currently, wisent protection programs are aimed at preserving the genetic diversity by establishing a germplasm bank. The objective of this study was to comprehensively characterize the morphology, morphometry and functionality of wisent epididymal spermatozoa and evaluate the effectiveness of their cryopreservation in extender based on Tris buffer and chicken egg yolk. The median total number of spermatozoa obtained from one individual was 1985.0 × 106 (62.5 × 106-7452.0 × 106). These gametes were characterized by median: 40.0% (0.5-70.0%) subjective motility, 69.8% (32.5-90.0%) viability and 54.3% (10.5-83.3%) normal morphology. The sperm head had a median size of 5.0 μm (3.5-6.7 μm) width, 8.5 μm (6.4-11.3 μm) length and 36.9 μm2 (23.7-48.6 μm2) surface area. The viable population of the obtained gametes was characterized by median values 53.2% (4.5-80.3%) of intact sperm membrane, 50.8 (26.0-76.6%) of intact acrosome, 0.4% (0-98.7%) of fragmented chromatin, 5.9% (0.0-88.8%) of cells with high mitochondrial potential and 42.1% (8.3-63.7%) without lipid peroxidation. The viable population of the frozen/thawed gametes was characterized by median values: 18.4% (2.4-57.9%) of intact sperm membrane, 35.1 (11.9-56.7%) of intact acrosome, 0.07% (0-89.2%) of fragmented chromatin, 12.8% (0.0-49.7%) of cells with high mitochondrial potential and 16.3% (2.2-53.6%) without lipid peroxidation. Due to the material originating from a relatively large number of wild individuals, the research presented here contributed to the description of certain species standards for the assessment of wisent epididymal spermatozoa. The presented effect of cryopreservation on these gametes justifies the use of an extender based on Tris buffer with the addition of chicken egg yolk. The obtained effects are satisfactory from the point of view of preserving valuable genetic material and their use in ART.
摘要：
死后获得的附睾精子被认为是遗传物质的宝贵来源，通常会不可避免地丢失。这使得这些配子构成了保护和恢复计划的关键要素。明智的(野牛，Linnaeus1758）是一种在自然栖息地灭绝后在动物园中幸存下来的物种。这导致整个种群的遗传范围缩小，目前只有12个祖先。目前,明智的保护计划旨在通过建立种质资源库来保护遗传多样性。这项研究的目的是全面表征形态学，明智的附睾精子的形态计量学和功能，并基于Tris缓冲液和鸡蛋黄评估其在延伸剂中冷冻保存的有效性。从一个个体获得的精子总数中位数为1985.0×106（62.5×106-7452.0×106）。这些配子的特征是中位数：40.0％（0.5-70.0％）主观运动性，69.8%(32.5-90.0%)的存活率和54.3%(10.5-83.3%)的正常形态。精子头的中位尺寸为5.0μm（3.5-6.7μm）宽度，8.5μm（6.4-11.3μm）的长度和36.9μm2（23.7-48.6μm2）的表面积。获得的配子的可行种群的特征是完整精子膜的中值为53.2％（4.5-80.3％），完整顶体的50.8（26.0-76.6％），0.4％（0-98.7％）的碎片染色质，5.9％（0.0-88.8％）的细胞具有高线粒体电位，42.1％（8.3-63.7％）没有脂质过氧化。冷冻/解冻配子的可行种群的特征为中值：完整精子膜的18.4％（2.4-57.9％），完整顶体的35.1（11.9-56.7％），0.07%(0-89.2%)的碎片染色质，12.8％（0.0-49.7％）的细胞具有高线粒体电位，16.3％（2.2-53.6％）没有脂质过氧化。由于材料来自相对大量的野生个体，这里提出的研究有助于描述某些物种标准，以评估明智的附睾精子。对这些配子的冷冻保存效果证明了使用基于Tris缓冲液并添加鸡蛋蛋黄的补充剂是合理的。从保存有价值的遗传物质及其在ART中的应用的角度来看,所获得的效果是令人满意的。
