الفهرس | Only 14 pages are availabe for public view |
Abstract In this study, 120 freshwater fish (Oreochromis niloticus) were divided into 4 different groups, each in triplicate groups (n=10), and used to assess the pharmacological activity of ZnO-NPs as anti-bacterial, immunomodulatory and antioxidant agent. Initially, the antibacterial activity was detected in-vitro through the disk diffusion method. The results revealed a potent antibacterial activity, especially at 80 mg/kg of ZnO-NPs. Then, Pathogenicity test with pseudomonas aeruginosa was done. The clinical signs following the infection were also detected and the mortality rate was calculated. Administration of ZnO-NPs (80mg/kg) showed potent ability to protect the fish from mortality induced by I/P injection of P. aeruginosa. Blood samples were collected twice, on the 20th and 40th days to detect the effect of ZnO-NPs on some immune parameters including granulocyte, monocytes, lymphocytes and white blood cells (WBCs) count, immunoglobulin M and lysozyme. Finally, tissues for histopathology to detect the effect of ZnO-NPs on some key immune organs The oral administration of Zn-ONPs resulted in a significant increase in Albumin, globulin, total protein, lymphocyte, monocyte, immunoglobulin M , lysozyme activity and glutathione from the 20th to 40th days in infected tilapia. In contrast, the results of ALT, AST and MDA decreased from 20th to 40th days in groups exposed to 80mg/kg ZnO -NPs. In conclusion, ZnO-NPs showed significant antibacterial activity against P. aeruginosainfected tilapia fish either in-vitro or in-vivo as well as elevated the immunity of the fish against P. aeruginosa infection. |