The ionic ratio variations of milt fluid effected by spawning migration place in Caspian roach Rutilus frisii kutum

Seminal plasma chemical compositions affect quality or ability of sperm fecundity (including ability of motion and infiltration to ovum) in fish. In this study seminal plasma ionic ratio of Caspian roach were investigated in spawning migration places. In the second half of March (migration season) to be caughted 10 males with same age and size. The sperm samples were transformed in ice to Gorgan university central lab. Na+ and K+ ions was measured by flamephotometere، and Ca2+، Mg2 was measured by spectrophotometere. Na+ to K+ ratio at the spawning migration place were significant (P<0. 05). Na+ to Mg2+ ratio، K+ to Ca2+ ratio، K+ to Mg2+ ratio at the spawning migration place were significant (P<0. 01). Na+ to Ca2+ ratio and Ca2+ to Mg2+ ratio at Mahisefid (Rutilus frisii kutum) spawning migration place were not significant (P>0. 05). Also، Na+ to K+ ratio and K+ to Ca2+ ratio in Mahisefid broodstock migrated to Shiroud was more than Gorganroud and Tajan. Na+ to Mg2+ ratio and K+ to Mg2+ ratio in Mahisefid (Rutilus frisii kutum) broodstock migrated to Gorganroud was more than Tajan and Shiroud. In conclusion، the Mahisefid (Rutilus frisii kutum) broodstock migrated to shirood have the better semen quality than the other rivers.