Department of Aquaculture, Hungarian University of Agriculture and Life Sciences, Gödöllő, Hungary.
University of Lorraine, Research Unit Animal and Functionality of Animal Products, Team Domestication in Inland Aquaculture, Nancy, France.
Theriogenology. 2022 Jun;185:127-133. doi: 10.1016/j.theriogenology.2022.03.033. Epub 2022 Apr 1.
Eurasian perch is an important fish species for European aquaculture diversification, but the quality of reproduction still remains one of the main limitations for further industry development. In particular, the optimal condition to obtain the best quality of sperm is poorly understood. The aim of our study was to measure the possible effects of two experimental rearing temperatures (6 °C and the conventionally used 12 °C) and of hormonal stimulation, on the motility parameters (pMOT, VCL, VSL, LIN, ALH, BCF), osmolality and fertilizing capacity of Eurasian perch sperm at the end of the reproductive cycle. A prior untested, large-scale (5 mL cryotube and Polystyrene box) cryopreservation method was implemented using fresh sperm obtained from the two above mentioned temperature groups. Males were injected with 100 μg body weight kg sGnRHa. No significant difference was recorded between the two rearing temperatures and between the saline control and sGnRHa treated groups on the different features of sperm quality. A similar fertilization rate was monitored in all sGnRHa treated (6 °C: 69 ± 13%, 12 °C: 81 ± 11%) and saline control groups (6 °C: 79 ± 10%, 12 °C: 87 ± 4%). Correspondingly, no significant difference in hatching rate was observed in the sGnRHa injected (6 °C: 27 ± 9%, 12 °C: 40 ± 20%) and saline control (6 °C: 35 ± 18%, 12 °C: 36 ± 7%) males. However, a notable negative effect of freezing process on sperm movement was observed following thawing in both temperature groups. No significant difference in the motility parameters was measured between the two temperature groups following large-scale cryopreservation. Furthermore, a similar result was observed in the fertilizing capacity (6 °C: 79 ± 10%, 12 °C: 75 ± 8) of thawed sperm as well as in the hatching rate (6 °C: 52 ± 13%, 12 °C: 46 ± 19%). Our results indicate that fresh Eurasian perch sperm can tolerate a reduced rearing temperature following hormonal treatment. The adopted large-scale cryopreservation method could be used efficiently in the future for the fertilization of large amounts of Eurasian perch eggs following a precise standardization process.
欧鳊是欧洲水产养殖多样化的重要鱼类品种，但繁殖质量仍然是进一步发展产业的主要限制因素之一。特别是，获得最佳精子质量的最佳条件还不甚清楚。我们的研究旨在测量两种实验养殖温度（6°C 和传统使用的 12°C）和激素刺激对繁殖周期末期欧鳊精子活力参数（pMOT、VCL、VSL、LIN、ALH、BCF）、渗透压和受精能力的可能影响。使用来自上述两个温度组的新鲜精子实施了一种未经测试的、大规模（5 毫升冷冻管和聚苯乙烯盒）冷冻保存方法。雄性注射 100μg 体重 kg sGnRHa。在精子质量的不同特征上，两个养殖温度之间以及盐水对照组和 sGnRHa 处理组之间没有记录到显著差异。在所有 sGnRHa 处理组（6°C：69±13%，12°C：81±11%）和盐水对照组中监测到相似的受精率（6°C：79±10%，12°C：87±4%）。相应地，在注射 sGnRHa 的雄性（6°C：27±9%，12°C：40±20%）和盐水对照组（6°C：35±18%，12°C：36±7%）中孵化率没有观察到显著差异。然而，在两个温度组中，解冻后都观察到冷冻过程对精子运动的显著负面影响。在大规模冷冻保存后，两个温度组之间的运动参数没有差异。此外，在解冻精子的受精能力（6°C：79±10%，12°C：75±8%）和孵化率（6°C：52±13%，12°C：46±19%）方面也观察到类似的结果。我们的结果表明，经过激素处理后，新鲜的欧鳊精子可以耐受较低的养殖温度。所采用的大规模冷冻保存方法可以在未来通过精确的标准化过程有效地用于大量欧鳊卵的受精。
