Seminal Plasma Composition in Acipenser persicus: Effect of Stripping Frequency on Ionic Content and Osmolality

The seminal plasma composition including ionic content (mM L-1) and osmolality (mOsmol Kg-1), as well as their physiological correlations were studied in Acipenser persicus subjected to different stripping frequencies (three times at intervals of 12h after spermiation). The semen of 9 broodstocks was collected by hand stripping 24 hours after induction of spermiation through intramuscular injection of sturgeon pituitary extract. Average values of osmolality, Na+, K+, Cl-, Ca2+ and Mg2+ were 82.56 ± 8.1, 62.44 ± 6.82, 6.92 ± 0.88, 21.11 ± 5.41, 0.79 ± 0.03 and 0.51 ± 0.03 respectively. The osmolality of seminal plasma at the first stripping was higher than those at the second and third stripping (T-test, P<0.05). The concentrations of monovalent ions were higher than those of divalent ones. (T-test, P<0.001). Changes of Mg2+, Cl-, and Na+ were not the same as changes of other ions and osmolality, i.e., the concentrations decreased at second but increased at the third stripping. However, there were no significant differences observed between ion concentrations at different strippings (T-test, P>0.05).