Biochemical Changes in Tissues of Wistar Albino Rats Following Exposure to Diet Incorporated with Locally Processed Fish

Biochemical changes in tissues of Wistar albino rats following exposure to feed formulated with different percentage concentrations (5%, 10%, and 20%) of smoked fish after 28 days were investigated. Albino rats fed with animal feed without smoked fish served as the control. The concentrations of ascorbic acid, glutathione (GSH), total protein, albumin, globulin as well as the activities of catalase and lactate dehydrogenase (LDH) were determined/ assayed respectively, using standard methods. The results showed that there were no significant (p>0.05) differences in these parameters from rats fed with 5% smoked fish when compared to those of the control. However, there were a significant (p<0.05) decrease in the concentrations of ascorbic acid, glutathione, total protein, albumin, globulin and the activity of catalase in albino rats fed with feed formulated with 20% in contrast to increase in activity of lactate dehydrogenase in smoked fish-fed rats when compared to the control. The values obtained showed that, as the percentage of smoked fish in the formulated feed increased from 10%, the concentrations of ascorbic, glutathione and total protein (albumin and globulin) decreased. The catalase activity decreased in contrast to lactate dehydrogenase whose activity increased, indicating that the changes were concentration-dependent. The results obtained might in part indicate that the local process of smoking of fish, which involved high temperature and smoke could have induced synthesis of harmful substances probably [polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines (HAAs)] in the smoked fish. These harmful substances might have caused the observed changes in the concentrations and activities of these oxidative stress parameters in the rats.