Study on the changes of some physiological factors during osmoregulation of juvenile Persian sturgeons (Acipenser persicus)

Experimental trials of acclimatization of juvenile Persian sturgeon, Acipenser persicus to different salinites of 0,5,10, 15ppt were studied. The juvenile Persian sturgeons in three weight classes (1.5, 3, 5g) have been  transfered from freshwater to different concentrations of saline water.  Na+, k+, Cl- concentrations of blood serum and the changes in the number and size of chloride cells were measured. Na+ concentration showed an imperceptible trend and K+ concentration had a decreasing one size of changed chloride cells in different salinities were 8.6-13±0.3 μm and their numbers were (25-65±3) in 5 pairs of fillaments. The results revealed that salinity tolerance was increased with the fish size. According to this study, there is a direct relation between the number and size of chloide cells and salinities and time exposure.