Varela Junior A S, Corcini C D, Ulguim R R, Alvarenga M V F, Bianchi I, Corrêa M N, Lucia T, Deschamps J C
Centro de Biotecnologia, Faculdade de Veterinária - Universidade Federal de Pelotas - UFPel, Campus Universitário s/n - Caixa Postal 354 - 96010-900 - Pelotas - RS - Brazil.
Anim Reprod Sci. 2009 Oct;115(1-4):323-7. doi: 10.1016/j.anireprosci.2008.11.002. Epub 2008 Nov 11.
Egg yolk is included in extenders for semen cryopreservation due to its protective effect against cold shock, which is attributed to the presence of low density lipoprotein (LDL). This study evaluates how semen quality is affected by using LDL as a replacement for egg yolk in extenders for cooled and frozen dog semen. In Experiment 1, semen was extended in TRIS-glucose at 5 degrees C, in four treatments: 20% egg yolk (T1); 6% (T2); 8% (T3); and 10% LDL (T4). Sperm motility and membrane integrity after 24, 48, 72 and 96 h and the 50% conservation rate of motile spermatozoa (50 M) were evaluated. The 50 M was less for T1 than for the other treatments (P<0.01), but T2-T4 did not differ (P>0.05). In Experiment 2, glycerol at 10% was included in the freezing extender, in treatments similar to those from Experiment 1. Sperm motility and membrane integrity did not differ for T2, T3 and T4 at any period in Experiment 1 and after thawing in Experiment 2 (P>0.05), but were greater for all LDL treatments than for T1 (P<0.01), in both experiments. Thus, LDL can replace egg yolk in the composition of the TRIS-glucose extender for cooled or frozen dog semen.
由于蛋黄对冷休克具有保护作用，精液冷冻保存稀释液中会添加蛋黄，这种保护作用归因于低密度脂蛋白（LDL）的存在。本研究评估了在犬精液冷藏和冷冻稀释液中使用LDL替代蛋黄对精液质量的影响。在实验1中，精液在5摄氏度下用TRIS-葡萄糖进行稀释，分为四种处理：20%蛋黄（T1）；6%（T2）；8%（T3）；10%LDL（T4）。评估了24、48、72和96小时后的精子活力和膜完整性以及活动精子的50%保存率（50M）。T1组的50M低于其他处理组（P<0.01），但T2-T4组之间无差异（P>0.05）。在实验2中，冷冻稀释液中添加了10%的甘油，处理方式与实验1类似。在实验1的任何时间段以及实验2解冻后，T2、T3和T4组的精子活力和膜完整性均无差异（P>0.05），但在两个实验中，所有LDL处理组的精子活力和膜完整性均高于T1组（P<0.01）。因此，在TRIS-葡萄糖稀释液的组成中，LDL可以替代蛋黄用于犬精液的冷藏或冷冻保存。
