College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
College of Fisheries, Key Lab of Freshwater Animal Breeding, Ministry of Agriculture, Huazhong Agricultural University, Wuhan, Hubei 430070, China; Shuangshui Shuanglu Institute, Huazhong Agricultural University, Wuhan 430070, China; National Demonstration Center for Experimental Aquaculture Education, Huazhong Agricultural University, Wuhan 430070, China.
Environ Pollut. 2019 Oct;253:749-758. doi: 10.1016/j.envpol.2019.07.082. Epub 2019 Jul 16.
The effect of selenium (Se) on the reproductive system has been investigated in both humans and vertebrates, but few studies of female fertility and reproduction in invertebrate have been reported. This study is aimed to investigate the effect of SeMet on growth performance and reproductive system after crayfish were fed with graded levels of dietary SeMet (0, 1.49, 3.29, 10.02, 30.27 or 59.8 μg Se/g dry weight) for 60 days. Crayfish treated with the high levels of SeMet (10.02, 30.27 and 59.76 μg Se/g) exhibited decreasing FW and CL in both male and female. Interestingly, Se accumulation was higher in ovary than in other tissues, suggesting that ovary may serve as a target organ for Se accumulation. We found that dietary Se concentration of 10.02 μg Se/g significantly improved the spawning rate, promoted the synchronized spawning, and up-regulated the expressions of mRNA of cdc2 and vitellogenin, with significantly increased E2 and VTG concentrations in hemolymph of female crayfish. However, a marked decrease of the E2 contents and spawning rate was observed in the groups treated with 30.27 and 59.76 μg Se/g diets. In conclusion, the results of this study indicated that the Se had maximum accumulation in ovary, affecting the reproductive capacity by intervening the expression of cdc2 and vitellogenin in the reproductive system. The LOAEL to induce FW was observed in crayfish fed with 10.02 μg Se/g diet, and its value can cause toxicity within the range of natural concentration, so the addition of Se in the feed should be within 10.02 μg Se/g.
硒（Se）对人类和脊椎动物生殖系统的影响已得到广泛研究，但关于无脊椎动物雌性生育力和生殖的研究较少。本研究旨在探讨蛋氨酸硒（SeMet）对连续投喂不同水平 SeMet （0、1.49、3.29、10.02、30.27 或 59.8μg Se/g 干重）60 天后克氏原螯虾生长性能和生殖系统的影响。结果显示，高 SeMet 处理组（10.02、30.27 和 59.76μg Se/g）的克氏原螯虾雌雄亲虾的体重和体长均显著降低。有趣的是，卵巢中的 Se 积累量高于其他组织，表明卵巢可能是 Se 积累的靶器官。我们发现，饲料 Se 浓度为 10.02μg Se/g 可显著提高产卵率，促进同步产卵，并上调亲虾卵巢中 cdc2 和卵黄蛋白原的 mRNA 表达，同时显著增加雌虾血淋巴中 E2 和 VTG 的浓度。然而，在 30.27 和 59.76μg Se/g 组中，E2 含量和产卵率显著降低。综上所述，本研究结果表明，Se 在卵巢中最大程度积累，通过干预生殖系统中 cdc2 和卵黄蛋白原的表达来影响生殖能力。10.02μg Se/g 饲料喂养的克氏原螯虾的 FW 出现 LOAEL，其值在自然浓度范围内可引起毒性，因此饲料中添加 Se 应控制在 10.02μg Se/g 以内。
