Macedo S, Bliebernicht M, Carvalheira J, Costa A, Ribeiro F, Rocha A
Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal.
CECA- Centro de Estudos de Ciência Animal, CECA/ICETA, Universidade do Porto, Porto, Portugal.
Reprod Domest Anim. 2018 Apr;53(2):519-524. doi: 10.1111/rda.13140. Epub 2018 Jan 30.
Glycerol-based extenders are widely utilized for freezing equine semen, but media combining methylformamide may better preserve sperm motility and mitochondrial function. Semen is cryopreserved utilizing either a Styrofoam box filled with liquid nitrogen or an automatic freezer. The objective of this experiment was to compare the post-thaw characteristics of the same ejaculates cryopreserved in a Styrofoam box or in an automatic freezer, utilizing a glycerol-based extender (Gent) and an extender that combines methylformamide and glycerol (BotuCrio ). For that, one ejaculate from 30 stallions collected in two different centres was used. For data analysis, a mixed linear model with laboratory, medium and freezing method and respective interactions as fixed effects was used. Stallion was taken into account as a random effect. There was no influence (p > .05) of laboratory, while stallion effect was marked. Semen frozen in BotuCrio in the automatic freezer had higher (p < .001) VCL than semen cryopreserved in Gent using the Styrofoam box. VCL was also higher (p = .068) for semen frozen in BotuCrio in the Styrofoam box than for semen cryopreserved in Gent using the same method. The difference between percentage of sperm with intact plasma membrane frozen in Gent using the Styrofoam box (44.43% ± 2.44%) compared to spermatozoa cryopreserved in BotuCrio using the same method (40.78% ± 2.42%) approached significance (p = .0507). The percentage of sperm with intact acrosome membrane was higher (p < .05) in semen frozen in BotuCrio (79.08% ± 1.79%) than semen frozen in Gent (75.15% ± 1.80%). A higher (p = .0125) percentage (32.24% ± 2.18%) of semen extended in Gent and cryopreserved in the Styrofoam box had high mitochondrial membrane potential than semen frozen in BotuCrio using the same method (26.02% ± 2.15%). Fertility studies are warranted to assess whether differences found have any effect on the fertility of inseminated mares.
基于甘油的稀释液被广泛用于冷冻马精液，但结合了甲酰胺的培养基可能能更好地保存精子活力和线粒体功能。精液冷冻保存可使用装满液氮的泡沫塑料盒或自动冷冻机。本实验的目的是比较使用基于甘油的稀释液（Gent）和结合了甲酰胺与甘油的稀释液（BotuCrio），在泡沫塑料盒或自动冷冻机中冷冻保存的同一射精样本解冻后的特征。为此，使用了从两个不同中心采集的30匹种马的一份射精样本。数据分析采用混合线性模型，将实验室、培养基、冷冻方法及其各自的交互作用作为固定效应。种马作为随机效应考虑在内。实验室因素无影响（p > 0.05），而种马效应显著。在自动冷冻机中用BotuCrio冷冻的精液，其曲线速度（VCL）高于用泡沫塑料盒以Gent冷冻保存的精液（p < 0.001）。在泡沫塑料盒中用BotuCrio冷冻的精液，其VCL也高于用相同方法以Gent冷冻保存的精液（p = 0.068）。用泡沫塑料盒以Gent冷冻保存的具有完整质膜的精子百分比（44.43% ± 2.44%）与用相同方法以BotuCrio冷冻保存的精子（40.78% ± 2.42%）之间的差异接近显著（p = 0.0507）。用BotuCrio冷冻的精液中具有完整顶体膜的精子百分比（79.08% ± 1.79%）高于用Gent冷冻的精液（75.15% ± 1.80%）（p < 0.05）。用Gent稀释并在泡沫塑料盒中冷冻保存的精液中，具有高线粒体膜电位的精液百分比（32.24% ± 2.18%）高于用相同方法以BotuCrio冷冻保存的精液（26.02% ± 2.15%）（p = 0.0125）。有必要进行生育力研究，以评估所发现的差异是否对授精母马的生育力有任何影响。
