Effects of 5 ml straws cryopreservation on the quality and ultrastructure of boar semen / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate damages to the quality of boar sperm frozen in 5 ml straws, pellet and 0.25 ml straws as well as the ultrastructural changes of frozen boar sperm in 5 ml straws.</p><p><b>METHODS</b>We compared 3 different freezing packages of 5 ml straws, pellet and 0.25 ml straws to determine their effects on frozen boar semen, and observed the morphological and ultrastructural changes of the boar sperm in the 5 ml straws using scanning electron microscopy.</p><p><b>RESULTS</b>In the 5 ml straws, the vitality and motility of the boar sperm after freezing were not significantly different from those in the other two formulations, the normal apical ridge (NAR) was 52.65%, higher than in the pellet but not significantly different from that in the 0.25 ml straws, and the sperm membranes were mostly bubbly, some locally broken, which indicated the damage induced by freezing and thawing.</p><p><b>CONCLUSION</b>At the present time, boar semen frozen in 5 ml straws were not significantly different from those frozen in 0.25 ml straws. The existing freezing-thawing method may cause certain damage to the quality and ultrastructure of boar sperm, and therefore needs to be further improved.</p>

Application of spindle-view in the enucleation porcine of oocytes / 生物工程学报

The Spindle-view, a specialized instrument for observing spindle image, was applied to observe the meiotic spindles of vitro matured porcine oocytes at 36, 42, 44, 48h, and enucleation from porcine, comparing to the previously methods (McGrath-Solter's method and two-step-squeezing method) in the enucleated. The results showed that: (1) there was no noticeable differences at vicinity of spindle images and 1st polar body among in vitro matured porcine oocytes at 40-48 h under the instrument; (2) Spindle-view is suitable for the observation of meiotic spindles of matured oocytes and enucleation from porcine; the modified Spindle-view method for enucleation is significantly better than McGrath-Solter' s method and two-step-squeezing method in the enucleated rates (95.5%, 42.1%, 74.2%, P < 0.0l) of absolutely removing nuclei matter; (3) the spindle images could be used to monitor the oocyte qualities.

Advances in Porcine Intracytoplasmic Sperm Injection / 中国生物工程杂志

Intracytoplasmic sperm injection,which combined with in vitro fertilization and micromanipulation techniques,has been applied to research the molecular mechanisms of fertilization,and produce the sexing livestock and transgenic animals.The research advances in porcine intracytoplasmic sperm injection,including in vitro maturation and pretreatment of oocytes,selection and treatment of spermatozoon,artificial activation of injected oocytes after injection,and improvement of the operation technique were reviewed.