Department of Gamete and Embryo Biology, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland.
URBE, Institute of Life, Earth & Environment, Université de Namur, Namur, Belgium.
Fish Shellfish Immunol. 2020 Jun;101:143-151. doi: 10.1016/j.fsi.2020.03.057. Epub 2020 Mar 27.
Hormonal induction of spermiation, previously reported to be immunogenic in fishes, is a common hatchery practice in pikeperch, Sander lucioperca. The aim of the present study was to investigate the effects of repeated induction of spermiation in pikeperch, following application of either human chorionic gonadotropin (hCG) or salmon gonadoliberine analogue (sGnRHa) on sperm quality indices as well as on immune and stress response. Mature males of pikeperch (n = 7 per group) were stimulated twice with five days between injections of either hCG (hCG; 500 IU kg), sGnRHa (sGnRHa; 50 μg kg) or NaCl (control group; 1 ml kg) to assess spermatozoa motility with a computer-assisted sperm analysis (CASA) system. During second sampling, blood plasma was sampled for humoral innate immune (peroxidase and lysozyme activities, ACH50), stress (cortisol, glucose) and endocrine (testosterone) markers. In addition, the head kidney was dissected to assay the expression of several immune genes (such as il1, c3, hamp, tnf-α and lys genes). The results indicate that hormonal treatment significantly increased sperm production. Sperm sampled after the hormonal treatment maintained its quality throughout the study, regardless of the sampling time. However, it appears that the application of hCG induced elevated cortisol and glucose plasma levels compared to the control group. Almost all immune markers, except the relative expression of hepcidin (hamp gene), were unaffected by the two hormones applied. The results showed that the induction treatment of spermiation processes in pikeperch resulted in an important physiological stress response for which the intensity varied according to the hormonal agent used. However, this stress response (more profound following application of hCG) was weakly associated with innate immune functions. On the other hand, a significant negative correlation between the expression of several important immune markers (peroxidase activity, relative expression of c3 and il1 genes) and sperm quality indices indicates significant involvement of immune status on sperm quality. The results obtained shed light on immune-system-induced modifications to sperm quality. The data presented here highlight the need for careful revision of broodstock management and selection practices where welfare status as well as individual predispositions of fish to cope with the stress should be taken under the consideration.
精子发生的激素诱导以前被报道在鱼类中具有免疫原性，是梭鲈（Sander lucioperca）中常见的孵化场实践。本研究的目的是研究在重复应用人绒毛膜促性腺激素（hCG）或鲑鱼促性腺激素释放激素类似物（sGnRHa）诱导精子发生后，对精子质量指数以及免疫和应激反应的影响。成熟的雄性梭鲈（n =每组 7 只）每隔五天接受两次注射，注射物分别为 hCG（hCG；500 IU kg）、sGnRHa（sGnRHa；50μg kg）或 NaCl（对照组；1 ml kg），以使用计算机辅助精子分析（CASA）系统评估精子运动能力。在第二次采样期间，从血浆中采样以测定体液先天免疫（过氧化物酶和溶菌酶活性、ACH50）、应激（皮质醇、葡萄糖）和内分泌（睾酮）标志物。此外，还解剖头肾以测定几种免疫基因（如 il1、c3、hamp、tnf-α 和 lys 基因）的表达。结果表明，激素处理显著增加了精子的产生。无论采样时间如何，经过激素处理后的精子在整个研究期间都保持其质量。然而，与对照组相比，hCG 的应用似乎会导致皮质醇和葡萄糖血浆水平升高。除了相对表达的铁调素（hamp 基因）外，几乎所有的免疫标志物都不受两种激素的影响。结果表明，在梭鲈中诱导精子发生过程的处理导致了重要的生理应激反应，其强度取决于所用的激素制剂。然而，这种应激反应（应用 hCG 后更为明显）与先天免疫功能的相关性较弱。另一方面，几个重要免疫标志物的表达（过氧化物酶活性、c3 和 il1 基因的相对表达）与精子质量指数之间存在显著的负相关，这表明免疫状态对精子质量有重要影响。获得的结果揭示了免疫系统对精子质量的修饰。这里呈现的数据强调了需要仔细审查亲鱼管理和选择实践，在这些实践中，应该考虑到鱼类的福利状况以及个体应对压力的倾向。
