Nöthling J O, Gerstenberg C, Volkmann D H
Department of Theriogenology, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa.
J Reprod Fertil Suppl. 1997;51:109-16.
Fifty-four semen samples from five dogs were evaluated both, fresh and after thawing. Some of these semen samples were mixed with autologous prostatic fluid after thawing and used to inseminate each of nine bitches 4-7 times intravaginally. All bitches conceived and the mean number (+/- SD) of conceptuses, number of corpora lutea and ratio between conceptuses and corpora lutea (implantation rate) were 5.7 +/- 2.8, 9.4 +/- 1.1 and 0.63 +/- 0.34, respectively. The mean incidence of normal sperm morphology and progressively motile spermatozoa for all semen samples were 71.5 +/- 13.5% and 74.4 +/- 7.1%, respectively, in fresh semen and 52.0 +/- 18.5% and 53.4 +/- 12.6% in frozen-thawed semen. Extension rate was 1:3 for all semen samples and the mean sperm concentration after thawing was 12.08 +/- 6.66 x 10(7) ml-1. The only semen quality variables after thawing that were correlated with implantation rate were the number of spermatozoa inseminated on day-2 and number of progressively motile spermatozoa inseminated on day-2 (where day 0 is the day of onset of dioestrus as determined by cytology) (Spearman's rank correlation coefficient > 0.7, n = 9, P < 0.05). This study suggests that it is essential that frozen-thawed semen is inseminated on day-2 and that an insemination dose of 10-11 x 10(7) progressively motile frozen-thawed spermatozoa is adequate to achieve a mean implantation rate of 75% or higher. The incidence of either proximal or distal cytoplasmic droplets in fresh semen was negatively correlated with motility after thawing in three of five dogs (Spearman's rank correlation < -0.5, n = 6-17, P < 0.05). Neither the percentage spermatozoa with normal morphology in fresh semen nor the percentage progressively motile spermatozoa in fresh semen nor the concentration of spermatozoa after thawing were correlated with motility after thawing. Fresh semen quality, with the exception of the incidence of retained cytoplasmic droplets, has little value in predicting the progressive motility after thawing in frozen dog semen.
对来自5只公犬的54份精液样本进行了新鲜状态及解冻后的评估。其中一些精液样本在解冻后与自体前列腺液混合，并用于对9只母犬进行4 - 7次阴道内授精。所有母犬均受孕，平均着床胚胎数（±标准差）、黄体数以及着床胚胎与黄体的比例（着床率）分别为5.7±2.8、9.4±1.1和0.63±0.34。所有精液样本新鲜时正常精子形态和进行性运动精子的平均发生率分别为71.5±13.5%和74.4±7.1%，冻融后分别为52.0±18.5%和53.4±12.6%。所有精液样本的稀释比例均为1:3，解冻后的平均精子浓度为12.08±6.66×10⁷/ml⁻¹。解冻后唯一与着床率相关的精液质量变量是第2天授精的精子数量和第2天进行性运动精子的数量（其中第0天是通过细胞学确定的发情间期开始日）（斯皮尔曼等级相关系数>0.7，n = 9，P < 0.05）。本研究表明，冻融精液必须在第2天进行授精，并且10 - 11×10⁷个进行性运动的冻融精子的授精剂量足以实现75%或更高的平均着床率。在5只公犬中的3只，新鲜精液中近端或远端细胞质滴的发生率与解冻后的活力呈负相关（斯皮尔曼等级相关<-0.5，n = 6 - 17，P < 0.05）。新鲜精液中正常形态精子的百分比、新鲜精液中进行性运动精子的百分比以及解冻后精子的浓度均与解冻后的活力无关。除了残留细胞质滴的发生率外，新鲜精液质量在预测冻融犬精液解冻后的进行性活力方面价值不大。
