Abstract：
The present work aims to evaluate the impact of Lake Manzala development, started in 2017, on lake water quality and biomarkers of Lake Oreochromis niloticus and Biomphalaria alexandrina samples from Dakahlia and Port Said during 2021 and compare it with the results of a series of studies concerning the same criteria in Lake Manzala during 2015. Results showed a remarkable increase in water EC, indicating a higher water exchange with the sea, a significant decrease in Pb, Cd, Cu, and Zn levels in water samples, and a remarkable decline in Cd and Pb bioaccumulation in all fish and snail samples. Macroinvertebrate samples showed higher taxa richness than in 2015, indicating biologically improved lake water quality. Results showed no trematode transmission, while there were natural infections in B. alexandrina snails during 2015. Biochemically, liver enzymes and hematological criteria in fish and snail samples during 2021 showed levels nearer to control at Port Said, indicating a less stressed liver and more healthy specimens than in 2015. Histopathological examination of fish organs (except spleen) and snail tissues pointed to their improved tissue architecture in Port Said than that of Dakahlia (2021). However, the 2021 samples were better than those of 2015. The immunohistochemical study showed higher expression of IL-6 in Dakahlia samples than the other samples, denoting higher tissue inflammation and humoral immune response. So, all the examined criteria indicated that Manzala Lake is positively impacted by the developmental and purification process, especially in Port Said.
摘要：
本工作旨在评估曼扎拉湖开发的影响，从2017年开始，对2021年Dakahlia和PortSaid的尼罗罗非鱼湖和AlexandrinaBomphalaria样品的湖泊水质和生物标志物进行了研究，并将其与2015年Manzala湖中有关相同标准的一系列研究结果进行了比较。结果显示水EC显著增加，表明与大海的水交换较高，铅的显著减少，Cd,Cu,和水样中的锌含量，所有鱼类和蜗牛样品中Cd和Pb的生物累积显着下降。大型无脊椎动物样品显示出比2015年更高的分类单元丰富度，表明湖泊水质在生物学上得到了改善。结果显示没有吸虫传播，而在2015年，B.alexandrina蜗牛有自然感染。生物化学,2021年鱼类和蜗牛样本中的肝酶和血液学标准显示，在塞得港，表明肝脏压力较小，标本比2015年更健康。鱼类器官（脾脏除外）和蜗牛组织的组织病理学检查表明，它们在赛义港的组织结构比Dakahlia（2021）的组织结构有所改善。然而,2021年的样本好于2015年的样本。免疫组织化学研究显示IL-6在Dakahlia样品中的表达高于其他样品,表示较高的组织炎症和体液免疫反应。所以,所有检查的标准都表明，曼扎拉湖受到发育和净化过程的积极影响，尤其是在塞得港。
