Changes in Ionic Ratios of Seminal Plasma and its Effect on Sperm Characteristics in Caspian Roach (Rutilus rutilus caspicus) During Spawning Migration

In this study, changes of ionic ratios (Na+to K+, Na+to Ca+2, Na+to Mg+2, K+to Ca+2, K+to Mg+2and Ca+2to Mg+2) during spawning migration of roach and its effect on sperm motility traits (sperm movement duration, percentage of motile spermatozoa) and sperm production characteristics (spermatocrit, sperm density and sperm volume) were investigated. Sperm of 30 males was collected during the spawning migration (February, March and April). Ionic ratios of Na+to K+, Na+to Ca+2 and Ca+2 to Mg+2 significantly changed (P<0.05) between three terms, but Na+to Mg+2, K+to Ca+2and K+to Mg+2ratios did not show significant differences (P>0.05) between February, March and April. The results suggested that sperm movement duration is slightly influenced by (P<0.05) Na+to K+ratio. A similar tendency was observed in values of spermatocrit and percentage of motile spermatozoa due to Na+to Ca2+ratio. Also, Ca+2to Mg+2ratio influenced percentage of motile spermatozoa. The present study describes that biochemical composition (Ionic ratios) and semen characteristics will help in development of the basic knowledge and the strategies during artificial spawning programmes in this species.