Varner D D, Blanchard T L, Meyers P J, Meyers S A
Department of Large Animal Medicine and Surgery College of Veterinary Medicine Texas A&M University College Station, TX 77843-4475 USA.
Theriogenology. 1989 Oct;32(4):515-25. doi: 10.1016/0093-691x(89)90273-2.
A breeding trial was conducted to evaluate the effect of in vitro storage time and temperature on fertilizing capacity of equine spermatozoa. Semen obtained from one stallion and diluted with skim milk-glucose extender was used to artificially inseminate 45 estrussynchronized mares. The mares were assigned to one of three treatment groups (15 mares per group): 1) insemination with fresh semen (collected within 0.5 h of use), 2) insemination with semen stored for 24 h at 20 degrees C or 3) insemination with semen stored for 24 h at 5 degrees C. The mares were inseminated daily during estrus, from the detection of a 35-mm follicle until ovulation, with 250 x 10(6) progressively motile spermatozoa (based on initial sperm motility of fresh semen). Semen samples (n = 35) were evaluated prior to insemination for percentages of total sperm motility (TSM), progressive sperm motility (PSM) and sperm velocity (SV). Single-cycle 15-d pregnancy rates. resulting from insemination with fresh semen, from fresh semen stored for 24 h at 20 degrees C or from semen stored for 24 h at 5 degrees C were the same (11 15 ; 73%). Mean diameters (mm) of 15-d embryonic vesicles were not different (P>0.05) among these three treatment groups (21.5 +/- 2.9, 19.6 +/- 2.6 and 20.5 +/- 3.6, respectively). Ten pregnant mares were aborted on Day 15 of gestation for use in another project. The pregnancy status of the 23 remaining pregnant mares was again determined at 35 to 40 d and 55 to 60 d of gestation. No pregnancy losses occurred during this time period. Mean TSM percentages were different (P<0.05) among the three groups: the fresh semen percentage was 89 +/- 2, semen stored for 24 h at 20 degrees C was 57 +/- 11 and semen stored for 24 h at 5 degrees C was 80 +/- 6. Similar differences were found for mean PSM and SV. Semen storage at either 20 or 5 degrees C for 24 h had no apparent effect on the fertilizing capacity of the extended semen samples; however, the reduction in all motility parameters tested was more dramatic in semen stored at 20 degrees C than that stored at 5 degrees C.
进行了一项繁殖试验，以评估体外储存时间和温度对马精子受精能力的影响。从一匹种马采集精液，并用脱脂奶 - 葡萄糖稀释液稀释，用于对45匹发情同步的母马进行人工授精。母马被分为三个处理组之一（每组15匹母马）：1）用新鲜精液（使用前0.5小时内采集）进行授精，2）用在20摄氏度下储存24小时的精液进行授精，或3）用在5摄氏度下储存24小时的精液进行授精。在发情期，从检测到直径为35毫米的卵泡直至排卵，每天用250×10⁶条进行性运动的精子（基于新鲜精液的初始精子活力）对母马进行授精。在授精前评估精液样本（n = 35）的总精子活力（TSM）、进行性精子活力（PSM）和精子速度（SV）百分比。用新鲜精液、在20摄氏度下储存24小时的新鲜精液或在5摄氏度下储存24小时的精液进行授精所产生的单周期15天妊娠率相同（11/15；73%）。这三个处理组中15天胚胎囊泡的平均直径（毫米）没有差异（P>0.05）（分别为21.5±2.9、19.6±2.6和20.5±3.6）。10匹怀孕母马在妊娠第15天流产，用于另一个项目。在妊娠35至40天和55至60天再次确定其余23匹怀孕母马的妊娠状态。在此期间没有发生妊娠丢失。三组之间的平均TSM百分比不同（P<0.05）：新鲜精液的百分比为89±2，在20摄氏度下储存24小时的精液为57±11，在5摄氏度下储存24小时的精液为80±6。在平均PSM和SV方面也发现了类似差异。在20或5摄氏度下储存24小时对稀释精液样本的受精能力没有明显影响；然而，在20摄氏度下储存的精液中，所有测试的活力参数的降低比在5摄氏度下储存的精液更为显著。
