Effect of zinc toxicity on liver histology of Nile tilapia, Oreochromis niloticus

Scientific Research and Essays

Abdel-Warith¹ 

关键词:  ;    Nile tilapia;    Oreochromis niloticus;    liver;    histological changes;    LC50 of Zinc.;   

DOI  :  10.5897/SRE11.883

学科分类：社会科学、人文和艺术（综合）

来源: Academic Journals

【 摘 要 】

In the present study the toxic effects of zinc (Zn) on the liver structure of Nile tilapia,Oreochromis niloticuswere investigated. Additionally, we estimated whether Zn concentration and exposure period influence the degree and nature of histological changes in the liver of exposed fish. Two hundred and forty fish (the average weight was 24.30± 2.85 g) were distributed randomly in twenty four glass aquaria (80 L) with stocking density of 10 fish for each. The aquaria were divided into two groups: the first group was exposed to 2, 4 and 6 mg/L of ZnCl2which represent 0.25, 0.50 and 0.75 of Zn LC50 respectively for one week (short exposure period); while the second group was exposed to the same concentrations of ZnCl2with the same replicates for 4 weeks (long exposure period). In addition, control group were not exposed fish to ZnCl2(0.00 LC50) were stocked with three replicates for each period. Fish mortality was significantly increased in a dose-dependent manner, without any significant effect of the exposure duration. Histological changes in the liver included hepatocyte degeneration, nuclear pycnosis, cellular swelling, and congestion of blood vessels. There was a marked difference in these changes among the different treatments of Zn concentrations in addition to the intensity of histological changes were however influenced by the extent of exposure period.

【 授权许可】

CC BY