Defective sperms cause fertilization failure under both in vivo and in vitro conditions. Therefore, providing optimal conditions during semen storage is a prerequisite for maintaining viability. The current study investigated bull semen quality in vitro and in vivo when zinc (Zn) nanoparticles were used as antioxidant during semen processing and cryopreservation. In total, 32 ejaculates were collected from four Holstein bulls. All ejaculates were pooled and diluted with Bioxcell-extender containing 0 (control group), 10⁻⁶, 10⁻⁵, 10⁻⁴, 10⁻³, and 10⁻² M of Zn nanoparticles. Several physical and biochemical sperm parameters were determined after freeze-thawing process. In vitro embryo development rate and pregnancy rate were monitored after in vitro fertilization or artificial insemination using semen treated with Zn nanoparticles. Plasma membrane integrity was improved (P < 0.05) in bull semen treated with 10⁻⁶ M (69.3%), and 10⁻² (62.4%) of Zn nanoparticles compared to untreated group (51.3%). In addition, proportions of live spermatozoa with active mitochondria were increased (P < 0.05) in semen supplemented with Zn nanoparticles at concentration of 10⁻⁶ M (67.3%), and 10⁻² (85.3%) compared to control group (49.8%). Moreover, the level of MDA was lower (P < 0.05) in semen with Zn nanoparticles at 10⁻⁶ M (2.97 mol/mL) and 10⁻² (2.7 mol/mL) concentrations than control semen samples (3.77 mol/mL). However, sperm total and progressive motility, sperm viability, DNA fragmentation, and pregnancy rate were not affected by treatment of semen with Zn nanoparticles. On the other hand, supplementation of in vitro maturation media with 10⁻⁶ M Zn nanoparticles has increased blastocyst rate (P < 0.05) compared to other experimental groups, while addition of Zn nanoparticles-treated sperm during in vitro fertilization did not affect embryo development rate. In conclusion, supplementation of Zn nanoparticles to semen has improved its quality without affecting embryo development rate in vitro. However, in vitro embryo development rate was increased when Zn nanoparticles were supplemented to IVM media. This support the notion of Zn nanoparticles beneficial action on improving bovine gametes quality without affecting pregnancy rate.

在体内和体外条件下，有缺陷的精子都会导致受精失败。因此，在精液储存期间提供最佳条件是维持活力的先决条件。当前的研究调查了当锌（Zn）纳米粒子在精液加工和冷冻保存过程中用作抗氧化剂时在体外和体内的牛精液质量。总共从四头荷斯坦公牛身上收集了32粒射精。所有射精汇集并用Bioxcell-剂含有0（对照组），10稀释^-6，10 ^-5，10 ^-4，10 ^-3，10 ^-2 M的Zn纳米颗粒。冻融过程后确定了一些物理和生化精子参数。在体外受精或使用锌纳米粒子处理的精液进行人工授精后，监测体外胚胎发育率和妊娠率。与未治疗组（51.3％）相比， 用10 ^-6  M（69.3％）和10 ^-2（62.4％）的锌纳米颗粒处理的公牛精液的质膜完整性得到改善（P <0.05 ）。此外， 在补充了浓度为10 ^-6  M（67.3％）和10 ^-2的锌纳米颗粒的精液中，具有活性线粒体的活精子的比例增加（P <0.05）（85.3％），而对照组（49.8％）。此外，浓度为 10 ^-6  M（2.97 mol / mL）和10 ^-2（2.7 mol / mL）的含锌纳米颗粒的精液中的MDA水平低于对照精液样品（3.77 mol / mL）（P <0.05 ） 。然而，精子的总和进行性运动，精子活力，DNA断裂和受孕率不受锌纳米颗粒精液处理的影响。另一方面，在体外成熟培养基中添加10 ^-6  M Zn纳米颗粒会增加胚泡率（P <0.05）与其他实验组相比，尽管在体外受精过程中添加Zn纳米粒子处理的精子不会影响胚胎发育速度。总之，在精液中添加Zn纳米粒子可改善其质量，而不会影响体外胚胎的发育速度。但是，当将锌纳米颗粒添加到IVM培养基中时，体外胚胎发育速率增加。这支持了锌纳米颗粒对提高牛配子质量而不影响怀孕率的有益作用。