Gacitua H, Arav A
Institute of Animal Science, Agricultural Research Organization, The Volcani Center, P.O. Box 6, Bet Dagan 50-250, Israel.
Theriogenology. 2005 Feb;63(3):931-8. doi: 10.1016/j.theriogenology.2004.05.012.
Artificial insemination with frozen-thawed buck semen shows variable results which depend on many factors related to semen quality and the cryopreservation processing. We conducted experiments based on a new freezing method, directional freezing, of large volumes (8 ml). In the first experiment semen from three Saanen bucks, ages 1-2-years-old and genetically selected for milk improvement, was frozen individually. Two to three-years-old Saanen females (n = 164) were synchronized with controlled internal drug release (CIDR), pregnant mare serum gonadotrophin (PMSG) and prostaglandin. Double cervical inseminations were performed with frozen-thawed semen and fresh semen as control. In the second experiment we used pooled, washed frozen semen to examine the effect of washed seminal plasma. The motility after washing was 80-90% and after thawing was 55-65% for all bucks. The sperm concentration increased with the collections and the advance into the breeding season from 1.9 x 10(9) to 4.4 x 10(9) cell/ml average. Two inseminations were carried out at 8h intervals. The first insemination was performed at 32 h after CIDR withdrawal with fresh and frozen-thawed semen. Pregnancy rates were assessed by ultrasonography conducted 40 and 90 days post-insemination (from three bucks). Results were 58, 67, 50% with fresh semen, and for frozen semen were 33, 37 and 53%; these results were significantly different in one of the three bucks (P < 0.005). In the second experiment with pooled, washed semen the pregnancy rate was 41.6%, which compared with the average results of the frozen semen in the first experiment 38.9% no significant difference was found. We conclude that freezing buck semen in large volumes (8 ml) is possible. Cryobanking of buck semen will facilitate a genetic breeding program in goats and preservation of biodiversity. Washed semen did not improve the fertility of the semen when Andromed bull extender is used.
用冷冻解冻后的公鹿精液进行人工授精，结果存在差异，这取决于许多与精液质量和冷冻保存处理相关的因素。我们基于一种新的大体积（8毫升）定向冷冻方法进行了实验。在第一个实验中，分别冷冻了三只1至2岁、经基因筛选以改良产奶性能的萨能公鹿的精液。对两到三岁的萨能母羊（n = 164）采用控制内部药物释放（CIDR）、孕马血清促性腺激素（PMSG）和前列腺素进行同期发情处理。用冷冻解冻后的精液和新鲜精液作为对照进行双宫颈授精。在第二个实验中，我们使用混合、洗涤后的冷冻精液来研究洗涤后的精浆的作用。所有公鹿的精液洗涤后的活力为80 - 90%，解冻后的活力为55 - 65%。精子浓度随着采精次数以及进入繁殖季节而增加，平均从1.9×10⁹个细胞/毫升增至4.4×10⁹个细胞/毫升。每隔8小时进行两次授精。第一次授精在取出CIDR后32小时，分别用新鲜精液和冷冻解冻后的精液进行。在授精后40天和90天（来自三只公鹿）通过超声检查评估妊娠率。新鲜精液的妊娠率分别为58%、67%、50%，冷冻精液的妊娠率分别为33%、37%、53%；在三只公鹿中的一只中，这些结果存在显著差异（P < 0.005）。在第二个使用混合、洗涤精液的实验中，妊娠率为41.6%，与第一个实验中冷冻精液的平均结果38.9%相比，未发现显著差异。我们得出结论，大体积（8毫升）冷冻公鹿精液是可行的。公鹿精液的冷冻保存将有助于山羊的遗传育种计划和生物多样性的保护。当使用安多芬公牛稀释液时，洗涤后的精液并未提高其生育能力。
