Histomorphometric and biochemical studies on the liver of rainbow trout (Oncorhynchus mykiss) after exposure to sublethal concentrations of phenol

Phenolic compounds are common water pollutants and include a wide variety of organic chemicals. The effects of three sublethal concentrations of phenol on liver histology and some biochemical parameters of Oncorhynchus mykiss after 8 weeks exposure were investigated in this study. A total of 80 rainbow trout (O. mykiss) were randomly divided into four groups (n = 20). Control group was kept in water without any add-on material, while experimental groups were exposed to the concentration of 0.6, 1.2 and 2.4 mg/L of phenol solution. At the end of the study period, the weight of liver, condition factor (CF) and hepatosomatic index (HSI) were measured. Tissue and blood samples were taken separately for histologic evaluation and serum biochemical parameters assay, respectively. In fish treated with phenol, significant reduction in liver weight, CF, HSI ratio, diameter of hepatocytes and hepatocytes nuclear diameter (p