Cryopreservation of fish and amphibian eggs is still an unsolved problem. The formation of ice crystals inside and outside cells acts as a main detrimental factor during a deep freezing of fish eggs, as well as crystal growth (recrystallization and repeated crystallization). Designing efficient cryoprotective media is necessary in order to avoid egg injury from freezing. Additional components that are present in a cryoprotective medium and reduce the thermomechanical stress and cracks of frozen tissues might increase oocyte survival after freezing–thawing. Natural components of eggs and the ovarian fluid are promising as such additives. The formation of ice microparticles was studied in thin layers (0.2 mm) of the ovarian fluid and components of Russian sturgeon egg homogenates upon their cooling to a liquid nitrogen temperature (–196°C). The processes of freezing, ice cracking, and microparticle formation were observed as the temperature was decreased gradually. The shape and size of ice microparticles were found to depend on the composition of the freezing solution. Certain fractions of egg homogenate were assumed to be suitable as components of a cryoprotective medium.

中文翻译：

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在冷却至 –196°C 期间，未受精俄罗斯鲟鱼卵的卵巢液和匀浆中冰微粒的形成

鱼类和两栖动物卵的冷冻保存仍然是一个悬而未决的问题。细胞内外冰晶的形成是鱼卵深度冷冻以及晶体生长（重结晶和重复结晶）过程中的主要不利因素。设计有效的冷冻保护介质是必要的，以避免卵子因冷冻而受伤。存在于冷冻保护介质中并减少冷冻组织的热机械应力和裂纹的其他成分可能会增加冻融后卵母细胞的存活率。鸡蛋的天然成分和卵巢液作为此类添加剂很有前景。在冷却至液氮温度 (–196°C) 后，研究了卵巢液和俄罗斯鲟鱼卵匀浆成分的薄层 (0.2 毫米) 中冰微粒的形成。随着温度的逐渐降低，观察到冻结、冰裂和微粒形成的过程。发现冰微粒的形状和大小取决于冷冻溶液的组成。鸡蛋匀浆的某些部分被认为适合作为冷冻保护介质的组分。