Effect of different levels of salinity with salt of Urmia Lake on growth, survival, carcass composition and some serum parameters of Caspian kutum (Rutilus kutum)

In this study, the effect of different salinity levels with salt of Lake Urmia was investigated on growth performance, body composition and some serum biochemical parameters of juveniles Caspian Kutum (Rutilus kutum). Fish with initial average weight of 1.05 ± 0.05g (±SD) were fed for 8 weeks in rearing tank. Juveniles Caspian Kutum were divided into four groups and treated with following preparation: control group salinity 0 ppt (fresh water), first treatment (salinity 5 ppt), second treatment (10 ppt) and third treatment (15 ppt). The results showed that the highest weight gain was observed in treatment 1 (p<0.05). Also, the Condition factor had significant differences between control and treatment 1 with other treatments (p<0.05). Survival was not affected by different salinity (p> 0.05). There was no significant difference in blood cholesterol levels between the experimental treatments, but there was a significant difference in hematocrit and glucose parameters (p<0.05). Body composition analysis showed that the experimental treatments had a significant effect on protein and fat levels but the moisture and ash levels were not affected by the experimental treatments. Generally, salinity level of 5 to 10 ppt of Urmia Lake salt had positive effect on growth, survival and blood parameters of juveniles Caspian kutum.