Abstract：
This study evaluated the effect of sperm concentration of boar semen doses on their capacity to maintain its motility over the thermo-resistance test (TRT; sperm resilience) and verified if the extender type (short or long-term) could influence this effect. Thirty ejaculates from five crossbred mature PIC® boars were used, and a factorial design was followed to produce semen doses with 1.5 billion cells in 45 or 90 mL, using Beltsville Thawing Solution (BTS) or Androstar® Plus (APlus). Then, low-concentration doses (16.7 × 106 cells/mL in 90 mL) and higher-concentration doses (33.3 × 106 cells/mL in 45 mL) with BTS or APlus were produced and stored at 17 °C for 168 h. At 72 h, during the TRT, the low-concentration doses (16.7 × 106 cells/mL) lost three-fold less motility than doses with 33.3 × 106 cells/mL (P < 0.01), regardless of the extender type (11. 5% vs. 30.5% of initial motility, respectively). Similar results were found when the TRT was carried out at 168 h, with low-concentration doses losing two-fold less motility (11.4%) than highly concentrated doses (25.9%; P < 0.01). No sperm concentration effect was observed on membrane integrity or mitochondrial membrane potential (P ≥ 0.23). The osmolarity was not affected by the sperm concentration (P = 0.56), only by the extender and the storage time (P < 0.01). In conclusion, the sperm concentration effect on sperm quality was not influenced by extender type, and the data suggest that a low concentration of semen doses positively affects sperm resilience.
摘要：
这项研究评估了公猪精液剂量的精子浓度对其通过耐热性测试（TRT；精子弹性）维持其运动能力的影响，并验证了延长剂类型（短期或长期）是否会影响这种效果。使用了来自五只杂交成熟PIC®公猪的30种射精，然后进行析因设计，在45或90毫升中产生15亿个细胞的精液剂量，使用Beltsville解冻溶液(BTS)或Androstar®Plus(APlus)。然后，用BTS或ABlus产生低浓度剂量(90毫升中16.7×106个细胞/毫升)和较高浓度剂量(45毫升中33.3×106个细胞/毫升)，并在17℃下储存168小时。在72小时，在TRT期间,低浓度剂量（16.7×106细胞/mL）的运动比33.3×106细胞/mL的剂量少三倍（P<0.01），无论扩展器类型如何(11.5%vs.初始运动性的30.5%，分别)。当TRT在168小时进行时，发现了类似的结果，低浓度剂量比高浓度剂量（25.9%；P<0.01）减少2倍的运动性（11.4%）。未观察到精子浓度对膜完整性或线粒体膜电位的影响（P≥0.23）。渗透压浓度不受精子浓度的影响（P=0.56），仅取决于扩展器和存储时间（P<0.01）。总之,精子浓度对精子质量的影响不受延伸剂类型的影响，数据表明，低浓度的精液剂量对精子弹性有积极影响。
