Millán de la Blanca María Gemma, Martínez-Nevado Eva, Castaño Cristina, García Juncal, Bernal Berenice, Toledano-Díaz Adolfo, Esteso Milagros Cristina, Bóveda Paula, Martínez-Fresneda Lucía, López-Sebastián Antonio, Santiago-Moreno Julián
Department of Animal Reproduction, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, (INIA) 28040 Madrid, Spain.
Zoo-Aquarium Madrid, 28011 Madrid, Spain.
Animals (Basel). 2021 Jan 15;11(1):203. doi: 10.3390/ani11010203.
The American flamingo is a useful model for the development of successful semen cryopreservation procedures to be applied to threatened related species from the family Phoenicopteridae, and to permit genetic material banking. Current study sought to develop effective sperm cryopreservation protocols through examining the influences of two permeating cryoprotectants and the seminal plasma removal. During two consecutive years (April), semen samples were collected and frozen from American flamingos. In the first year, the effect of two permeating cryoprotectants, DMA (dimethylacetamide) (6%) or MeSO (dimethylsulphoxide) (8%), on frozen-thawed sperm variables were compared in 21 males. No differences were seen between DMA and MeSO for sperm motility, sperm viability, and DNA fragmentation after thawing. In the second year, the role of seminal plasma on sperm cryoresistance was investigated in 31 flamingos. Sperm samples were cryopreserved with and without seminal plasma, using MeSO (8%) as a cryoprotectant. The results showed that samples with seminal plasma had higher values than samples without seminal plasma for the following sperm variables: Straight line velocity (22.40 µm/s vs. 16.64 µm/s), wobble (75.83% vs. 69.40%), ( < 0.05), linearity (62.73% vs. 52.01%) and straightness (82.38% vs. 73.79%) ( < 0.01); but acrosome integrity was lower (55.56% vs. 66.88%) ( < 0.05). The cryoresistance ratio (CR) was greater in samples frozen with seminal plasma than without seminal plasma for CR-progressive motility (138.72 vs. 54.59), CR-curvilinear velocity (105.98 vs. 89.32), CR-straight line velocity (152.77 vs. 112.58), CR-average path velocity (122.48 vs. 98.12), CR-wobble (111.75 vs. 102.04) ( < 0.05), CR-linearity (139.41 vs. 113.18), and CR-straightness (124.02 vs. 109.97) ( < 0.01). This research demonstrated that there were not differences between MeSO and DMA to successful freezing sperm of flamingos; seminal plasma removal did not provide a benefit for sperm cryopreservation.
美洲红鹳是开发成功的精液冷冻保存程序的有用模型，该程序可应用于红鹳科受威胁的相关物种，并用于建立遗传物质库。当前的研究试图通过研究两种渗透性冷冻保护剂和去除精浆的影响来开发有效的精子冷冻保存方案。在连续两年的4月，收集了美洲红鹳的精液样本并进行冷冻。第一年，比较了21只雄性美洲红鹳中两种渗透性冷冻保护剂DMA（二甲基乙酰胺）（6%）或MeSO（二甲基亚砜）（8%）对冻融后精子变量的影响。解冻后，DMA和MeSO在精子活力、精子存活率和DNA片段化方面没有差异。第二年，在31只红鹳中研究了精浆对精子抗冻性的作用。使用MeSO（8%）作为冷冻保护剂，对有精浆和无精浆的精子样本进行冷冻保存。结果表明，对于以下精子变量，有精浆的样本的值高于无精浆的样本：直线速度（22.40µm/s对16.64µm/s）、摆动率（75.83%对69.40%）（P<0.05）、线性度（62.73%对52.01%）和直线性（82.38%对73.79%）（P<0.01）；但顶体完整性较低（55.56%对66.88%）（P<0.05）。对于CR-前向运动性（138.72对54.59）、CR-曲线速度（105.98对89.32）、CR-直线速度（152.77对112.58）、CR-平均路径速度（122.48对98.12）、CR-摆动率（111.75对102.04）（P<0.05）、CR-线性度（139.41对113.18）和CR-直线性（124.02对109.97）（P<0.01），有精浆冷冻的样本的抗冻率（CR）高于无精浆冷冻的样本。这项研究表明，MeSO和DMA在成功冷冻红鹳精子方面没有差异；去除精浆对精子冷冻保存没有益处。
