Department of Ichthyology and Aquaculture, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 5, 10-719 Olsztyn, Poland.
Department of Ichthyology and Aquaculture, University of Warmia and Mazury in Olsztyn, ul. Oczapowskiego 5, 10-719 Olsztyn, Poland.
Anim Reprod Sci. 2021 Jan;224:106648. doi: 10.1016/j.anireprosci.2020.106648. Epub 2020 Nov 13.
The initial experiment of this study was conducted to determine whether sex steroid concentrations varied before, during and after the reproductive season of European grayling (Thymallus thymallus L.) farmed broodstock confined in a recirculation aquaculture system (RAS). The results indicated that the plasma sex steroid (testosterone - T, progesterone - P and estradiol - E) concentrations varied (P < 0.05) during these reproductive periods. There were greater concentrations of T, P and E before and during the grayling reproductive season indicating there are important functions of these steroid hormones associated with gonadal maturation, gamete production and reproductive behavior during the spawning period. In the second experiment of this study, the effectiveness of European grayling controlled reproduction treatment regimens was analyzed and there were 34.69 % and 68.18 % having ovulations in the 2 and 3-year-old broodfish, respectively. Of the embryos developing to the eyed-egg stage, there were 3.70 % and 6.87 % derived from eggs of 2- and 3-year-old grayling females, respectively. Proportions of embryos developing from the eyed-egg stage to hatching were 38.1 % and 52.1 % from eggs of 2- and 3-year-old grayling females, respectively, when there was culturing in a RAS. The results indicate that with grayling broodfish there is greater efficacy in induction of reproduction when there is imposing of the controlled reproduction treatment regimen on 3- rather than 2-year-old broodfish.
本研究的初始实验旨在确定养殖于循环水产养殖系统（RAS）中的欧洲红点鲑（Thymallus thymallus L.）亲鱼在繁殖季节前后的生殖季节，其生殖类固醇浓度是否存在变化。结果表明，这些生殖期的血浆生殖类固醇（睾酮-T、孕酮-P 和雌二醇-E）浓度存在差异（P<0.05）。在红点鲑的生殖季节之前和期间，T、P 和 E 的浓度更高，这表明这些类固醇激素在生殖期间与性腺成熟、配子产生和生殖行为有关，具有重要作用。在本研究的第二个实验中，分析了欧洲红点鲑控制性繁殖处理方案的有效性，2 龄和 3 龄亲鱼的排卵率分别为 34.69%和 68.18%。在发育到眼点期的胚胎中，分别有 3.70%和 6.87%来自 2 龄和 3 龄雌鱼的卵子。当在 RAS 中进行培养时，来自 2 龄和 3 龄雌鱼卵子的胚胎从眼点期发育到孵化的比例分别为 38.1%和 52.1%。结果表明，在红点鲑亲鱼中，当对 3 龄而不是 2 龄亲鱼施加控制性繁殖处理方案时，繁殖的诱导效果更好。
