Institute for Reproduction of Farm Animals Schönow, Bernau, Germany.
Setor de Suínos, Faculdade de Veterinária, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Reprod Domest Anim. 2022 Nov;57(11):1327-1335. doi: 10.1111/rda.14208. Epub 2022 Jul 26.
This study evaluated the effect of different proportions of dead spermatozoa on the quality of liquid boar semen during a thermo-resistance test (TRT). After 3 days of storage (17°C), 54 conventional artificial insemination semen doses (~23 × 10 sperm/ml in ~88 ml of BTS) were split into three 15 ml-treatments (25%, 50%, and 75% dead sperm cells) by mixing two subsamples containing 75% (I) and 0% (II) of live cells. Spermatozoa were evaluated after TRT at 30 (on-test) and 300 min (off-test) incubation at 38°C. At the on-test, treatments of 25%, 50%, and 75% dead sperm cells showed medians for total sperm motility of 77.6%, 50.2%, and 25.6%, respectively. Considering the absolute variation of sperm motility during TRT, doses with 25% dead sperm lost more percentage points (pp) (-9.4 pp) compared to doses containing 50% (-8.2 pp) and 75% dead sperm (-4.5 pp). The lowest loss was observed for doses with 75% dead sperm (p < .01). However, data showed that treatments lost similar proportion of motile cells over the TRT: 25% dead sperm = -11.9%, 50% dead sperm = -16.0%, and 75% dead sperm = -17.5% (p = .31). Regarding the flow cytometry parameters (plasma and acrosomal membrane integrity, mitochondrial activity of cells with intact plasma membrane, high degree of lipid disorder, and apoptotic cells), the absolute variations did not surpass values of -1.8, 3.4, -5.4, and 4.7 pp, respectively. Furthermore, the relative variation suggested that dead sperm did not substantially change their values over the TRT. In conclusion, dead sperm cells did not influence the quality of contemporary live cells during the period and in conditions of a TRT.
本研究评估了不同比例的死精子对热耐受试验（TRT）期间液态公猪精液质量的影响。在储存 3 天后（17°C），将 54 份常规人工授精精液剂量（约 23×10 个精子/ml，在约 88ml 的 BTS 中）分成三个 15ml 处理（25%、50%和 75%死精子），通过混合含有 75%（I）和 0%（II）活细胞的两个亚样本。在 38°C 下孵育 30（试验中）和 300（试验后）分钟后，对精子进行 TRT 评估。在试验中，25%、50%和 75%死精子细胞的处理分别显示总精子活力中位数为 77.6%、50.2%和 25.6%。考虑到 TRT 期间精子活力的绝对变化，含有 25%死精子的剂量比含有 50%（-8.2 pp）和 75%死精子（-4.5 pp）的剂量损失更多的百分点（pp）（-9.4 pp）。损失最少的是含有 75%死精子的剂量（p<.01）。然而，数据表明，在 TRT 过程中，处理组失去了相似比例的活动细胞：25%死精子=-11.9%，50%死精子=-16.0%，75%死精子=-17.5%（p=.31）。关于流式细胞术参数（质膜和顶体膜完整性、质膜完整细胞的线粒体活性、脂质紊乱程度高和凋亡细胞），绝对变化不超过-1.8、3.4、-5.4 和 4.7 pp，分别。此外，相对变化表明，死精子在 TRT 期间其值没有明显变化。总之，在 TRT 期间和条件下，死精子细胞不会影响当代活细胞的质量。
