Mamdouh Samar, Mohamed Ayman Saber, Mohamed Haggag Ali, Fahmy Wafaa Soliman
Zoology Department, Faculty of Science, Cairo University, Cairo, Egypt.
Biol Trace Elem Res. 2022 Jan;200(1):375-384. doi: 10.1007/s12011-021-02653-x. Epub 2021 Feb 28.
The release of heavy metals to the environment increased dramatically with industrialization and rapid economic development, and they have accumulated in aquatic organisms. The current study aimed toe valuate the physiological, immunological, and histological changes of crayfish (Procambarus clarkii) as bio-indicator for water quality. Crayfishes of the filed study group were collected from a polluted area (Rosetta branch, Egypt), where the highest concentration for heavy metals in water was for zinc (Zn). Besides the field study group, other crayfishes were exposed to different doses of ZnSO (0, 203, and 406 mg L) corresponding to Zn concentration (0, 46.03, and 92.06 mg L) respectively in aquariums for consecutive 4 days. Heavy metal concentrations in field water sample were arranged as follows: Zn > Fe> Pb > Cu and Mn > Ni > Co > Cd. The result revealed that Zn bioaccumulation increases significantly with the increase of water Zn concentration among the tested groups compared to the control group, where the highest bioaccumulation in all studied tissues (hepatopancreas, gills, and muscles) was observed in the field group and Zn high-dose group. Also, there was a significant increase in the levels of hemolymph uric acid, urea, creatinine, glucose, aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase. Their highest concentrations were observed in the Zn high-dose group and the field group, while the levels of total protein, albumin, and cholesterol showed a significant decrease among the tested groups as compared with the control group. Their determined lowest concentrations were in the Zn high-dose group and field group. Among tested groups, total hemocytes and granulated hemocytes decreased significantly while hyaline hemocytes increased as compared with the control group. Histological damages were observed in hepatopancreas, gills, and muscles in the field and Zn groups. The present study showed that exposure to Zn caused physiological and histological changes in Procambarus clarkia. We assumed that Procambarus clarkia could be used as a sensitive bioindicator for monitoring water quality criteria.
随着工业化和经济的快速发展，重金属向环境中的释放急剧增加，并且它们在水生生物中积累。当前的研究旨在评估小龙虾（克氏原螯虾）作为水质生物指示物的生理、免疫和组织学变化。实地研究组的小龙虾采集自一个污染区域（埃及罗塞塔支流），该区域水中重金属浓度最高的是锌（Zn）。除了实地研究组，其他小龙虾在水族箱中连续4天分别暴露于不同剂量的硫酸锌（0、203和406毫克/升），对应的锌浓度分别为（0、46.03和92.06毫克/升）。实地水样中的重金属浓度排列如下：锌＞铁＞铅＞铜，锰＞镍＞钴＞镉。结果显示，与对照组相比，在测试组中，随着水中锌浓度的增加，锌的生物积累显著增加，在实地组和高剂量锌组中，所有研究组织（肝胰腺、鳃和肌肉）中的生物积累最高。此外，血淋巴尿酸、尿素、肌酐、葡萄糖、天冬氨酸转氨酶、丙氨酸转氨酶和碱性磷酸酶的水平也显著增加。它们的最高浓度出现在高剂量锌组和实地组，而与对照组相比，测试组中的总蛋白、白蛋白和胆固醇水平显著下降。它们确定的最低浓度出现在高剂量锌组和实地组。与对照组相比，测试组中的总血细胞和颗粒血细胞显著减少，而透明血细胞增加。在实地组和锌组的肝胰腺、鳃和肌肉中观察到组织学损伤。本研究表明，接触锌会导致克氏原螯虾发生生理和组织学变化。我们认为克氏原螯虾可以用作监测水质标准的敏感生物指示物。
