Tamer S. Imam*, Abdelhakeem El-Murr**

and Yasser AbdElhakim**

*Departments of Forensic Medicine and Toxicology, **
Department of Fish Diseases and Management, Faculty of Vet. Medicine, Zagazig University.

Correspondence authors: Yasser Abd Elhakim

Lecturer of Fish Disease and Management,

E-mail:[email protected]

Faculty of Veterinary Medicine, Zagazig University, 44511 Zagazig, Egypt.

Tel\: 00201024410724

Received 9/ 6/ 2015

Accepted 28/ 7/ 2015


The current experiment was carried out to evaluate the effects of different concentrations of the insecticide fipronil on the immune response and health condition of Nile tilapia fish (Oreochromis niloticus). For this purpose, immunological, biochemical and hematological parameters were assayed. Two hundred and forty O.niloticus fish were randomly assigned into four groups in triplicates: a control group and three fipronil treated groups in which fish exposed to 1/3 of 96 hrs LC50 for 4 days, 1/10 and 1/20 of 96 hrs LC50 of fipronil for 10 weeks respectively. The mortality rate in fish exposed to 1/3 LC50 for 4 days was 53%; meanwhile it was 21% and 8 % in those exposed to 1/10 and 1/20 of LC50 of fipronil for 10 weeks. Nervous manifestations, pale gills, congestion and hemorrhages of different internal organs were observed. There was a significant decrease in erythrocytic count, total leukocytic count, PCV% and Hb content. Also, reduced serum IgM level and lysozyme activity with a concurrent increase in the serum nitric oxide level were recorded. Obvious significant increase in serum AST, ALT, urea, creatinine and cortisol levels in all fipronil exposed groups when compared with control group. In addition, liver, gills and skin tissues revealed marked histopathological alterations.

Key words: Fipronil, O. niloticus, IgM, Lysozyme activity.