The effect of cations on sperm motility performance and fertilizing ability of silver carp Hypophtalmychtis molitrix

The objective of the study was to investigate the effect of saline solution containing cations (Na+, K+, Ca+2, Mg+2) on sperm motility performance (duration of sperm motility and percentage of motile spermatozoa) and fertilizing capacity of sperm (fertilization rate, hatching rate, larvae length during hatching, larvae length during active feeding and survival rate) in silver carp. The results suggested that solutions containing ions did not improve the duration of sperm motility. The same was observed for the percentage of motile spermatozoa. Fertilization rate influenced by solutions containing Ca+2, and other ions could not affect this parameter. The results showed that hatching rate was higher in solutions containing 99 mEq/L NaCl, 2 mEq/L MgCl2 and 2, 4 mEq/L CaCl2 respectively. Also, survival rate was higher in the solution containing 2 mEq/L MgCl2 and 36 mg/dL KCl respectively.With regard to the obtained results, it was concluded that using appropriate activation medium can improve quality of fish sperm and subsequently increases artificial reproduction performance.