Wu Xinyu, Wu Hao, Wu Yifan, Xu Zhiqiang, Shan Hong, Gao Tianheng
College of Oceanography, Hohai University, Nanjing 210024, China.
Freshwater Fisheries Research Institute of Jiangsu Province, Nanjing 210017, China.
Biology (Basel). 2025 Apr 11;14(4):407. doi: 10.3390/biology14040407.
Sediment improvers are important mediators of aquatic animals' growth performance and the surrounding environmental quality. However, the physiological responses of crayfish () to different sediment improvers remain unclear. Here, we cultivated crayfish using two chemical (potassium monopersulfate and potassium ferrate) and two biological (purple nonsulfur photosynthetic bacteria and ) sediment improvers at low and high concentrations. After 42 days, we found that the addition of chemical sediment improvers was more effective in improving water quality than biological sediment improvers (e.g., more stable pH and lower nutrient concentrations). By contrast, the application of biological sediment improvers resulted in considerably enhanced final weight, weight gains, and survival rates. In all low-concentration groups, the activity of immune-related enzymes (e.g., superoxide dismutase and glutathione peroxidase) in the hemolymph and hepatopancreas considerably increased, whereas the malondialdehyde activity and mRNA expression of AMP genes ( and ) considerably decreased. Crayfish exposed to low concentrations of sediment improvers exhibited enhanced intestinal and hepatopancreatic integrity, with a thickened mucosal layer and increased density of epithelial cell granules. Additionally, the composition of the gut microbiota varied after the addition of different sediment improvers. In summary, our research indicated that different types of sediment improvers not only improved the farming environment but also had varying effects on crayfish. Therefore, an appropriate sediment improver based on specific aquaculture conditions is needed.
底质改良剂是水生动物生长性能和周围环境质量的重要调节因子。然而，小龙虾对不同底质改良剂的生理反应仍不清楚。在此，我们使用两种化学底质改良剂（单过硫酸钾和高铁酸钾）和两种生物底质改良剂（紫色非硫光合细菌和[此处原文缺失一种生物底质改良剂名称]），以低浓度和高浓度培养小龙虾。42天后，我们发现添加化学底质改良剂在改善水质方面比生物底质改良剂更有效（例如，pH更稳定，营养物质浓度更低）。相比之下，应用生物底质改良剂可显著提高最终体重、体重增加量和存活率。在所有低浓度组中，血淋巴和肝胰腺中免疫相关酶（如超氧化物歧化酶和谷胱甘肽过氧化物酶）的活性显著增加，而丙二醛活性和AMP基因（[此处原文缺失两个AMP基因名称]）的mRNA表达显著降低。暴露于低浓度底质改良剂的小龙虾肠道和肝胰腺完整性增强，黏膜层增厚，上皮细胞颗粒密度增加。此外，添加不同底质改良剂后，肠道微生物群的组成发生了变化。总之，我们的研究表明，不同类型的底质改良剂不仅改善了养殖环境，而且对小龙虾有不同的影响。因此，需要根据特定的水产养殖条件选择合适的底质改良剂。
