Journal of Aquatic Ecology

 In this study, the effects of salinity on the hematological parameters in Mesopotamichthys sharpeyi were investigated within 21 days. One hundred and twenty fish weighing 300-350g were divided randomly to four treatments of urban water and following 3 salinities: 4, 8 and 12 g/lit and blood samples were taken in following days of experiment: 1th, 3th, 7th, 14th and 21th.Hematological parameters were measured: white blood cell count (WBC), red blood count (RBC), Hb, RBC index (MCHC, MCH, MCV) and cortisol hormone.At the end of the experiment, compare of treatments with control group showed significant decrease in the total count of red blood cells in the salinity of 12 g/l (p<0.05). But no significant difference was observed in other hematological indices (p>0.05). Cortisol hormone showed significant variation among different treatments in different days (p<0.05). At the end of the experiment, the highest cortisolrates were observedin salinity of 4 gr/L (45.25±3.8) and the lowest cortisolrateswere observed in salinity of 8 gr/L (19.75±1.53).The results suggested that hematological parameters and cortisol hormone can be affected by salinity environment.